Ryohei Sasagawa is Kyoko'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 fired up and always wants to be a part of it. Due to Ryohei's enthusiasm, he often rushes into things without fully evaluating the situation, which often ends in his injury. He also has a short memory and forgets many important details, something his adult self solved by writing memo's. Ryohei is always hiding the truth of what he is doing from Kyoko due to an incident that happened when they were still 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 visibly concerned for Kyoko's safety, so he covers up his actual life-or-death battles with the cover story of "Sumo matches".
Ryohei was first introduced when Tsuna 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. Reborn has since then asked Ryohei to join the Vongola.
Ryohei was targeted by the Kokuyo gang due to his status as Namimori school's fifth strongest. He was badly injured by Ken and lost five teeth, resulting in him being hospitalized. He later lied to Kyoko about how he received his wounds.
Ryohei was chosen as the Guardian of the Sun and was given a half Vongola Ring. Collonello 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. Colonello then shot Ryohei with a special bullet that allowed him to use the Maximum Cannon.
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 preventing him from seeing (Lussuria already had sun glasses), then had both fists broken after punching Lussuria's metal knee. However, once Kyoko arrived, Ryohei was able to smash Lussuria's leg and end 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 and Gokudera from Mammon's illusion by destroying the entire gym with his Maximum Cannon.
In the Future, Ryohei had gone to work with the Varia in Italy. When he returned, he found Chrome, and brought her to the Vongola Hideout. He also brought along information concerning the plan to attack the Millefiore Family's Base. During the Melone Base invasion the group discovered Black Spell Nigella as he was finished off by White Spell Baishana. Ryohei was angered at Baishana's disloyalty and easily defeated him with his improved attack Maximum Ingram. Soon after when the Melone Base was activated, Ryohei and Gokudera were separated from Yamamoto and Lal Mirch and encountered Gamma. Ryohei who had tied up Gokudera up with Rope, in order to prevent him rushing into a fight, was knocked unconcious during his battle with Gamma. However thanks to the activation ability of Ryohei's Box Weapon, Kangaryu, Gokudera's Box Weapon grew up, giving him the upper-hand in the coming fight. Later Ryohei was switched to his Past self and along with the other Guardians received a Vongola Box Weapon.
When returning to the past for the Arcolabeno Trials, Ryohei was chosen, along with Tsuna and Yamamoto, to take part in Mammon's Test of Adaptability. Under the belief that Kyoko was being held hostage, the trio were forced to solve a series of riddles as well as fight a number of Box Weapons. After discovering that Kyoko was safe, they swiftly defeated Mammon and passed his trial. Later Ryohei and the other Guardians were assembled for Reborn's Trial of Leadership and were easily beaten by him. Shortly after, the Guardians joined forces with the other Arcobaleno, to fight Verde and his army.
Ryohei was later taught by Gokudera how to use the Rings and Box Weapons. He was adamant about keeping Kyoko in the dark about the Mafia, but after learning that her attendance to Choice was mandatory, forgave Tsuna after a single punch. After the Vongola lost the Choice battle, Ryohei healed Shoichi who had been fatally wounded in the fight.
After being sent back to the past to train the Guardians meent Giotto, who reveals that the 10th Generation Guardians have yet to inherit the true power of the Vongola. After Giotto leaves, Reborn states that he knows the procedure, and assigns tutors to all the Guardians. Reborn becomes Ryohei's tutor as they both have the Sun Flame. Later he encounteres Knuckle who appeared from the Vongola Sun Ring to ask him to voice his resolve, Knuckle happy with his respose, says he'll test Ryohei to the extreme as well.
Ryohei was later hurt while trying to save Uni 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 Hell Hole, Ryohei asked the others to sit back while he fought. By activating his Cambio Forma, Ryohei was able to take down Kikyo's defence but due to his previous injuries, he was unable to finish him off. 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.
After returning to the past, Ryohei soon got into a fight with Koyo Aoba, one of the transfer students from Shimon. He was grouped with Hibari, Koyo and Adelheid to patrol Namimori Middle School's thrid year building to protect Tsuna.
Abilities and Weapons
Ryohei 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. 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 Maximum Cannon, a blow strong enough to destroy buildings. The attack works by concentrating all the energy in his arms cells into one punch. Thus Ryohei keeps his right fist in perfect condition, for times of great disadvantage.
Future Ryohei's fighting skills have greatly improved. He can now use Lussuria's footwork and with it multiply the number of blows dealt with a regular Maximum Cannon, an attack called Maximum Ingram. His Dying Will Flame is powerful enough to self-destruct active Box Weapons and also heal himself in a short time using the Sun activation.
- 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 it's Activation ability to speed up the natural healing process. The Vongola Guardians were later granted their true forms by the First Vongola Boss.
- Sun Scalpel - Due to his Flame attribute Ryohei takes the position of medic as well as fighter. Using this Box Weapon he activates the cells in a body effectively speeding up the natural healing cycle. It has been shown to heal smaller wounds in seconds and even fatal injuries over time.
- Kangaryu (漢我流 lit. "My Way Of Honor") - His animal Box Weapon that releases a battle scarred kangaroo named Kangaryu. She imbues items in her pouch with Sun Dying Will Flames and the shoots them to Ryohei. The Sereno Gloves produced are weaved from vegetation that quickly heal wounds on Ryohei's fist. As well as this Kangaryu can shoot out boots that enable Ryohei to fly. Also any Box animals placed inside her pouch will grow up at an accelerated rate.
- Vongola Sun Kangaroo - Kangaryu now has a pair of turrets on her back which fire shots that greatly increase Ryohei's physical strength and speed. A normal person would be crushed by the level of the Flames but Ryohei can use it as he has an extremely high level of endurance. Nevertheless, Ryohei only has three minutes before his body becomes unable to take the strain. The bullets fired also cause Box Animals to grow up instantly. Kangaryu now also has her own pair of boxing gloves and Flame Boots. When Cambio Forma is activated, Kangaryu transforms into headgear and a pair of boxing gloves called the Knuckle of Maximum Break which was said to have been worn by the First Sun Guardian.
- Taienrankuga (Flame Storm Sky Fangs) - A combined attack with Gokudera and Basil. Kangaryu shoots Uri with a Sun bullet that increases its size and strength, while Alfin combines its Rain Flame with Uri's Storm Flame.
- Motorcycle/Airbike- Used to travel great distances without the use of Dying Will Flames, thus escaping detection.
Win Loss Battle Record
- vs Tsuna - Undetermined
- vs Ken - Lost
- vs Lussuria - Won
- (Future self) vs Baishana - Won
- (Future self) vs Gamma - Lost
- + Basil, Lambo, Tazaru and Nosaru vs Kikyo - Undetermined
- Tsuna refers to Ryohei as Big Brother just like Kyoko. He is also nicknamed "Lawn-Head," by Gokudera and refered to as Senpai by Yamamoto.
- His catchphrase is "Extreme" (kyoukugen).
- In the Reborn Fandom, he is referred to as number 33.
- Ever since he saw the Future I-Pin fighting, he gained a slight crush on her.
- 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.
- Ryohei has two character songs, Kyokugen Fighter and Hareta Sora wa Miagete.
- "Sereno" can be translated to "Calm" but is normally translated as "Clear Sky".
- 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.
- It is hinted that Ryohei may be romantically involved with Hana Kurokawa in the Future.
- Ryohei was one of the quickest Guardians to light his Flame and open his Box Weapon when coming to the Future.
- Ryohei was the last Vongola Guardian to appear in the future, the last to be replaced with his past self, and the last to reveal his Vongola Box's Cambio Forma.
- Openings Featured in: