Ryohei Sasagawa (笹川 了平, Sasagawa Ryōhei) is Kyoko Sasagawa's older brother who is obsessed with boxing. His motto is to live "to the extreme!", which he applies to everything he does. As such, he prefers to fight his opponents head on, seeing any disadvantage as a chance to improve his fighting skills. He even barged into a zoo, expecting to fight a bear, but ended up fighting a lion instead. Every time he sees Tsuna and his friends doing something strange, he gets riled up and wants to be a part of it. Due to Ryohei's enthusiasm, he often rushes into things without fully evaluating the situation, which often results in his injury. He also has a short memory and forgets many important details, something his future-self overcame by writing memos. Ryohei is always hiding the truth of his actions -the actions relating to the Mafia- from Kyoko, due to an incident that had happened while they were in primary school. Some high school students who did not like Ryohei used Kyoko to lure him into a trap. In his attempt to rescue her, he suffered severe injuries, which resulted in the scar on his left temple. Kyoko still feels responsible for this incident, though she accepts that he needs to fight. He is deeply concerned for Kyoko's safety, so he covers up his actual life-or-death battles with the cover story of "Sumo matches". He is known to have great boxing skills in the Vongola Famiglia.
Ryohei was first introduced when Tsunayoshi Sawada accidently pulled him to school while in Dying Will Mode. Ryohei was instantly inspired by Tsuna's spirit and urged him to join the boxing club. They later fought at the boxing club where they were both shot with the Dying Will Bullet. However it had no effect on Ryohei as he always lives his life to the limit. All his future appearances in this arc was to make Tsuna join the boxing club.
Ryohei was targeted by the Kokuyo gang due to his status as Namimori Middle School's fifth strongest. He was badly injured by Ken and lost five teeth, resulting in him being hospitalized. He later lied to his sister Kyoko as to how he received his wounds. Later, during the fight with Mukuro Rokudo, Ryohei was one of the people Tsuna saw while under the effect of the Criticism Shot.Guardian of the Sun and was given a half Vongola Ring. In order to prepare for the Varia's oncoming arrival, Colonnello became Ryohei's home tutor, and the two departed to a mountainous region. It is during this time that Ryohei trained by relaxing his body as opposed to exerting himself. Colonello also shot Ryohei with a special bullet that risked death but ultimately allowed him to unleash a mighty blow called Maximum Cannon. Later in the week Ryohei, Yamamoto and Gokudera, defended Lambo from Levi's Lightning Squad.
Before the battle Tsuna worried about Kyoko's reaction to her brother fighting, however after telling him about how he got his scar, Ryohei made him promise to keep it a secret from her. Later Ryohei became the first to fight, in the Sun Ring Battle against the Varia martial arts expert Lussuria. Ryohei who was immediately disadvantaged due to overhead floodlights in the Sun Arena, preventing him from seeing (Lussuria already had sunglasses), then had both fists broken after punching Lussuria's Metal Knee. However, once Kyoko arrived, Ryohei gained enough motivation to smash Lussuria's metal knee as well as his leg, ending his use of Muay Thai. Gola Mosca (after assuming his loss) then shot Lussuria leaving Ryohei the victor. During the Sky Ring Battle after being cured by Gokudera, Ryohei gave Lussuria the antidote despite being his opponent. He later saved Yamamoto, Chrome Dokuro and Gokudera from Mammon's illusion by destroying the entire gym with his Maximum Cannon. Later the Vongola Guardians forced the remaining Varia to surrender.Glo Xinia at Healthy Land and brought her to the Vongola Hideout. He also brought along information concerning the plan to attack the Millefiore Family's Base (as well as presents for the children). He later joined the others during the Melone Base invasion. The group were eventually discovered by Vice Captain Ginger Bread who claimed to be responsible for Colonello's death. Though greatly angered by this, Ryohei allowed Lal Mirch to fight. However he was revealed to be a puppet and the base was alerted. The group later found the Black Spell member Nigella as he was finished off by White Spell Baishana. Ryohei (angered at Baishana's disloyalty) crushed him with his own Tsuchinoko Box Weapon. Soon after the Melone Base was activated, Ryohei and Gokudera were separated from the others and encountered Gamma. Ryohei, who had tied Gokudera up in order to prevent him rushing into the fight, was knocked unconcious during his battle with Gamma. However, thanks to Kangaryu's activation ability, Gokudera's Box Weapon grew up, giving him the upper hand in the coming fight. Later, Ryohei was switched to his Past self in order to unite the Vongola Rings, creating a momentary force field around those present. Then (along with the other Guardians) Ryohei received a Vongola Box Weapon from his future self and had the situation explained to him. Reborn's Trial of Leadership and were easily beaten by him. Shortly after, the Guardians joined forces with the other Arcobaleno, to defeat Verde and his army.
Upon returning to the future, Ryohei was taught by Gokudera how to use the Rings and Box Weapons. He was adamant about keeping Kyoko in the dark about the Mafia, but upon learning that her attendance to Choice was mandatory, he forgave Tsuna after a single punch. After the Vongola lost the Choice battle, Ryohei healed Shoichi who had been fatally wounded in the fight.Kyoya Hibari's trial, Ryohei was adamant about convincing him to participate and followed him to the school roof. However, they were interrupted by Hibari's trainer, Skull, in his airship who, frustrated by Hibari's lack of interest, began to attack. During the battle Ryohei helped Hibari protect the school resulting in Hibari taking his trial in order to repay Ryohei, however First Sun Guardian (Knuckle) appeared from the Sun ring and announced that Ryohei had already passed his test due to standing against adversity without fear and convincing Hibari to participate. The First Cloud Guardian (Alaude) also appeared, stating that Hibari had also fulfilled his duty. Later, due to their involvement with the Mafia, Kyoko and the girls were trapped by the First Generation Mist Guardian (Daemon Spade) at Healthy Land. Ryohei and Lambo were separated from the others while attempting a rescue and were forced to fight doppelgangers of themselves. The illusion was then torn apart by Hibari's rampage. Yuni from the Six Funeral Wreaths. Despite this he flew up with Reborn in order to backup Tsuna leading to the Funeral Wreath's retreat. That night Ryohei agreed to protect Lambo in the coming battle. The next day the two of them along with Basil, Tazaru, and Nosaru encounted Kikyo at the lake. Ryohei then undid the light hypnosis on Lambo causing him to destroy Kikyo's army of Velociraptor di Nuvola with his Vongola Box. After Kikyo opened his Carnage Box, Ryohei asked the others to sit back while he fought. By activating his Cambio Forma, Ryohei was able to catch Kikyo of guard but due to his previous injuries, he was unable to defeat him. He then appeared to be defeated by Kikyo but was revealed to be an illusion created by Mukuro. Later during an all out battle between the Vongola and the Six Funeral Wreaths, Ghost suddenly appeared and Ryohei tried to combine an attack with Gokudera and Basil. However the attack passed straight through him and Ryohei (along with everyone else present) had his Dying Will Flames drained. The Vongola eventually defeated Byakuran and returned to the past. Koyo Aoba, one of the transfer students from Simon Middle School. After the Simon revealed themselves to be an allying mafia family Ryohei was grouped with Koyo in order to protect Tsuna. When no assassins arrived, Reborn made them compete with a set of puzzles on a plate made of extra hard ceramic which were too difficult for either of them. Reborn stated that the competition would have to be postponed if the puzzles were to break. Therefore, Koyo held the plate, while Ryohei broke it by using Maximum Cannon, which Koya was capable of receiving. Later Ryohei was the first to find Yamamoto after the attack and called the ambulance and started to heal him. However he noted that the wounds were too deep. During the Inheritance Ceremony, the Simon betrayed the Vongola and Ryohei (along with the other Guardian's) was defeated by Enma Kozato and his Ring was broken. However Talbot then appeared and repaired the Vongola Rings by combining them with the Vongola Box Rings. With Ryohei's resolve, his ring turned into Vongola Gear. Ryohei later joined Tsuna, Gokudera and Lambo as they invaded the Holy Land of the Simon. While traveling they were attacked by Koyo to whom Ryohei demanded a one on one boxing match, in a ring of Koyo's barbed Forest Flames. However, so much as placing a knee on the ground would result in a loss of their pride as boxers. Koyo then used his Flame to restrict Ryohei's movements and beat him from all angles but by using his Vongola Gear Ryohei was able to turn the damage he had received into his own power. However in the process Koyo's blacked out glasses were removed allowing him to use his eye sight to its full potential, though Ryohei was able to figure out Koyo's weakness and strike a critical blow. Despite his injuries Koyo was still standing and the two squared off in a match of endurance. After having each of his Killer Points destroyed by Koyo, Ryohei delivered a devastating attack at full power that cleared the forest. However the two remained standing, each refusing to admit defeat and after crossing fist's once more, both collapsed at the same time. The Vindice then arrive and imprisoned Ryohei and Koyo as they had both lost their pride. With his last words before vanishing into the portal, Ryohei encouraged Tsuna to find his own pride and to stick by it no matter what. After Daemon's defeat, he is set free, along with the Simon. Later, he is seen at school caught in Adelheid's nets with Koyo and Julie, for breaking school property in a spar with the former.
Ryohei appears with Tsuna at Chrome's welcoming party because Chrome was kicked out of Kokuyo Land. In the miming competition, he mimed I-Pin and Reborn, but was kicked off by Reborn, who told him to "get lost to the extreme!" while doing so.
Later, on the first day of the Representative Battle of the Rainbow, Ryohei happily heads to school with Tsuna. However, when the battle suddenly starts, he, Yamamoto, and Gokudera group up and try to find Tsuna. When an explosion occurs because of Tsuna being punched through the ceiling by Iemitsu (though they don't know the cause), they run towards the explosion; however, they are barred by Hibari and Fon, the former appearing to be Fon's representative, who states that he would bite all three of them to death.
Ryohei became impressed with Tsuna's strength in Dying Will Mode and as such tries to recruit him to his Boxing Club. Tsuna who is often scared of Ryohei's enthusiasm none the less treats him like a brother (calling him "Big Brother" like Kyoko). As a result of his feelings for Kyoko, Tsuna is often worried that Ryohei will get hurt in fights and tries to talk him out of them. After Tsuna revealed the truth about the Mafia to Kyoko, Ryohei struck him in rage. However Ryohei understood Tsuna's feelings and continues to respect him.
Colonnello became Ryohei's tutor during the Varia arc. Colonnello soon saw Ryohei's potential and claimed he would become stronger than the other Guardians. They both share extreme attitudes which helped strengthen their bond and after training with Colonnello, Ryohei has also become more reserved (though still maintains a level of enthusiasm). In the Future, Ryohei continued to look up to Colonnello and was greatly saddened by his death, though he remained mostly calm about it.
Ryohei respects Hibari's power and wants him to involve himself with the rest of the family just like when he tried to drag Hibari into circle group at Vongola Ring Battle. Hibari's lone nature often clashes with Ryohei's persistent one, which causes many arguments even if it is only for the smallest problem, though in the Inheritance Succession Arc, Ryohei was the only one who managed to convince Hibari to take his trial. Hibari also respects Ryohei enough not to interrupt his fights. In the Future, little has changed as Ryohei is still frustrated with Hibari's lack of co-operation and Hibari still ignores him but will always accept whenever Ryohei challenge him (When Hibari said that children are not allowed in his hideout, Ryohei got angry and challenge his because he thinks it's a big problem and Hibari agreed on doing so), though he sometimes invites Hibari to a drink, which is always refused, much to his disappointment.
As sporting fanatics, Ryohei and Yamamoto have great respect for one another (Yamamoto even referring to Ryohei as Senpai). Like with Yamamoto, Gokudera has an unnecessary rivalry with Ryohei and as he is easy to frustrate this often leads to pointless arguments where they are eventually separated by Yamamoto. The future Ryohei also admitted to Gokudera that they share a hot temper and need to learn to keep their cool. They seem to call each other different names, Gokudera calls Ryohei Lawn-head or Grassy, while Ryohei calls him Octopus-head. Despite this, Ryohei works well with both of them and all three support each other in their fights.
Weapons and AbilitiesRyohei is an excellent boxer who possesses great strength. His boxing training resulted in his proficiency in hand-to-hand combat, and ability to take and give a huge amount of physical punishment. Even the Dying Will Bullet, which increases a person's strength by removing the body's limiters, has no effect on him since he always lives "to the extreme". He has also perfected Lussuria's footwork allowing him to leave several after images to confuse opponents.
- Boxing: Ryohei uses boxing techniques to perform his other techniques.
- Extreme Rush: Ryohei punches a single target multiple times in rapid succession.
- Extreme Corkscrew Punch: Ryohei punches a target in such a manner that the area punched is distorted, as if it was corkscrewed.
- Maximum Cannon: During Ryohei's training, Colonnello shot him with a spiritually condensed bullet that risked death. By surviving Ryohei's potential was unlocked, enabling him to unleash a blow strong enough to destroy buildings.
- Maximum Ingram: While using Lussuria's footwork the number of blows dealt with a regular Maximum Cannon are multiplied.
- Maximum Combination: A high speed range of punches using both arms. While it is not as strong as other attacks, it is almost impossible to dodge.
- Sunshine Counter: It uses the damage previously taken and fires it in a blast of sun flames. The more damage taken before it is used, the more damage it deals. Once release, it takes the form of a burning sun, with solar flares coming out of it, and then it shoots in a direct blast that destroys anything it touches.
- Sunshine Uppercut: A powerful uppercut that can be powered up when more damage is taken prior to usage. Similar to Sunshine Counter, it creates the sun like figure and releases the blast, this time, raising instead
- Vongola Sun Ring: Won during the Sun Ring Battle. As part of the Tri-Ni-Set it is classed as S-rank. Ryohei is capable of releasing Sun Dying Will Flames from his Ring and use its Activation ability to speed up the natural healing process. Even though the Sun Flame is traditionally used for healing Ryohei has been shown to release them in massive amounts that overpower enemies. The Vongola Rings were later granted their true forms by the Vongola Primo; however, they were later broken by the Simon Famiglia.
- Kangaryuu (Version Vongola Box) : Ryohei's Box Weapon is a battle-scarred kangaroo, Kangaryuu (漢我流 lit. "My Way Of Honor"), that can release Sereno Gloves and Dying Will Flame Boots. When updated to her Vongola Box Form, Kangaryu gained a pair of turrets on her back, has her own Boxing Gloves and is capable of flight. When released from the Ryohei's Sun Bangle, Kangaryuu gained armor that covered her whole body but no longer needed the turrets to enter Cambio Forma.
- Bangle of the Sun Version X: Upgraded version of the Vongola Sun Ring combined with Garyuu's box ring.
- Knuckle's Maximum Break: Kangaryuu merges with Ryohei, to form the Weapon of the 1st Generation Vongola Sun Guardian, Knuckle, a pair of boxing gloves and head gear. In its Version X form it also includes a right shoulder armor, boots and tight armors.
- Dying Will Flame Boots: A device that allows Ryohei to fly by blasting him off emitting Sun flames through the soles. Ryohei is the only member of the Vongola Famiglia who uses them.
- Motorcycle/Airbike : Used to travel great distances without the use of Dying Will Flames, thus escaping detection.
- Sun Trowel: A scalpel that heals others' wounds over time.
- Tsuna refers to Ryohei as "big brother" (onii-san) just like Kyoko. He is also nicknamed "Turf Top," by Gokudera and Lambo and referred to as "Senpai" by Yamamoto.
- Ryohei and Knuckle both have the same Seiyu.
- His catchphrase is "Extreme" (kyoukugen).
- Ryohei is a horrible swimmer who sinks to the bottom and twitches. He is unaware of this and ironically works part-time as a lifeguard.
- Kangaryu's wounds are revealed to be the result of constant sparring with the Future Ryohei. Despite this, the two seem to be highly friendly towards each other.
- According to Reborn! artbook, Colore, he had gone to Hibari's house several times to challenge him but always ends up kicked out of the house by Hibari himself.
- His pride is that he always fights one on one as a boxer.
- According to Reborn in Haru Haru Interview: Dangerous, his weakness is when his sister (Kyoko) is crying.
- When he was shot with a Dying Will bullet in episode 7, he had a Sky flame instead of his normal Sun flame.
- Character Songs Featured In: