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Shoichi Irie (入江正一, Irie Shōichi), in the present, is shown as a 15-year-old boy who happens to meet Tsuna and his Family. Because Lambo was bazooka-ed into Shoichi's family's apartment, the Bovino Famiglia sends him a package of Lambo's stuff and a big amount of money, excusing Lambo for any annoyance that he caused. Not much is shown of him in the present, but in the Future, Shoichi was shown to be in close contact with Byakuran, being watched everywhere he went. He also was at first shown to be a fearful leader as the holder of the Sun Mare Ring. He was the reason why Tsuna, Lal, Gokudera, Yamamoto, and Future Ryohei went to the Melone Base so that they could take him out. After the Base was destroyed, along with the cameras, Shoichi told Tsuna and the gang, which now included Chrome, Kusakabe, Lambo, I-Pin, and Hibari, that he was on their side, and that this was a setup by Future Tsuna along with Future Hibari. Later, he was found out to only be the Fake Sun Funeral Wreath, not the real one.
Shoichi has red hair and wears glasses. He has a thin build.
Shoichi is anxious and has a somewhat bad temper, but is also a strong-willed and loyal person.
Shoichi's family receives a package after Lambo is bazooka-ed into their apartment. This package includes olive oil, pasta noodles, wine, and a wad of bills, as well as a pack of 10 Year Bazooka ammo for Lambo. Shoichi's mother and sister ask him to take the package back and comment that it should be a man's job to bring Lambo and it back to Reborn's place. He carries both the package and Lambo back to the residence. When he first gets there, he sees Bianchi sunbathing. He comments on this to his mother over his mother's cellphone and she says they must be foreign celebrities. When Reborn appears, looking nothing like Shoichi had imagined. At that moment Lambo wakes up, and attacks Reborn while still on Shoichi's shoulder, but the attack is once again deflected. After Lambo passes out from his wound, Shoichi flees, forgetting to leave the package. He relays what he learned to his mom over the phone, but she has been replaced by his sister because his mom couldn't make sense of what he said and decided to go shopping. Lambo again perks up, takes the grenades designated to him, and throws them at Reborn, who deflects the attacks, blowing Lambo up before Shoichi's eyes. When Tsuna appears, his hopes go up because he's a normal person. Then, Lambo blasts himself with the Ten-Year Bazooka not three feet from Shoichi, Bianchi sees Teen Lambo and tries to kill him, but is a horrible shot with a gun, and actually grazes Shoichi. Reborn blasts Tsuna with a Dying Will (Or Deathperation) Shot, and then a shot to both cheeks, or a 'Niramekko Shot,' causing his face to swell up, at which point young Irie passes out. However, Bianchi is 'not in the mood,' and attacks Tsuna with her poison cooking. Shoichi apparently runs back home, with the package, afterwards and has strange nightmares that he feels won't stop until he returns it.
As he explains in the future, the box had some hidden 10-Year Bazooka shells that Shoichi used to see how his life ended up. He reveals that because he changed the future to make it change to one of the other parallel futures. First, he goes to a future when he's at an engineering college and accidentally runs into Byakuran. He then changes it to where he becomes a musician, his dream job, and meets Byakuran again, giving him his power of connection with all other parallel Byakurans. Then he travels to the future many more times and sees the carnage Byakuran creates, no matter what change Shoichi does. So, he got himself back into the university to befriend Byakuran and erases his past self's memories with a five-year memory timer.
After first arriving in the Future, Future Gokudera tells Tsuna that after five minutes, he has to go back to the past and kill Shoichi.
Merone Base Invasion
When Tsuna was captured by Spanner, he and Reborn, who appeared as a hologram through Tsuna's headset, resolved for a much more aggressive goal, to capture Shoichi and force him to tell them everything he knew about time travel. However, at the end of the chapter, Shoichi reveals that he worked out a sophisticated plot to get to that point with Vongola X (Future Tsuna) and Future Hibari. He goes on to explain every detail of their plan. Byakuran sends out a hologram to explain that he suspected Shoichi of betrayal for a while, and about his secret elite team, the Real Six Funeral Wreaths. This was after Ryohei was brought to the future to cause the Vongola Rings to protect them all from the base exploding. Afterwards, Shoichi reveals what was really in the White Round Machine: the seven Vongola Guardians, along with the seven Vongola Boxes. Tsuna, after learning the truth, officially accepts him and Spanner into the Vongola.
Shoichi created choice with Byakuran in college as a game they made to pass the time. He, after siding with the Vongola, worked with Spanner to create their base. He is shown to be participating in Choice as a member of Tsuna's Family.
After the Dying Will Flames of the participants were decided, Shoichi received Byakuran's permission to count himself as a non-ring member. He announced that for the Vongola, Yamamoto and Gokudera would be their Rain and Storm combatants, Tsuna would be their Sky combatant, and himself and Spanner would be their non-ringed combatants. He was also selected by the Gyro Roulette as the Target for the Target Rule game over Spanner. A target reticule then appeared over his heart and his Sun Flame was forcibly drawn out, which caused him to drop to his knees as he cried out in pain. When Tsuna expressed his worry about his condition, he said that he could bear it because he was the one that made Byakuran that way.