The true identity of Il Re is Shiki.
This fact is known only to Arbitro and Rin at the start of the game, but is later found out by several other people. Emma reveals the truth about Il Re to Akira when she contacts Akira on Shiki's route, but she does not specify whether or not she knew from the start.
During most of the game, Il Re is closer to a figurehead, and Arbitro runs the general operations of Vischio. Even the name of “Il Re” was decided by Arbitro.
Shiki does not care about the organization, the drugs, or the money Vischio makes. He does not take a percentage of the profits as compensation. Instead, Shiki’s one demand is that Arbitro spread Line far and wide, so that Shiki can fight people who use it and confirm his strength.
The ultimate goal of Igura is to challenge Il Re and win riches and power. Shiki defends his title in Il Re battles. He is undefeated, and intentionally mythologized as rich and powerful to tempt people into joining Igura. To preserve the mystery of Il Re, the matches are private and have highly publicized results.
The battles are heralded by a pre-show that’s open to the public. These pre-shows are a source of major entertainment in Toshima and, as stated in the manga, are an element of Vischio’s control over the city.
In the series, Il Re battles are shown in plotlines involving Rin, who is the only main character who wins and steals his way to the tags needed to make the challenge. The pre-shows are more connected to Nano, who views them in both the game and manga.
Shiki holds the right to rule over Vischio not only because he is a powerful swordsman capable of defending the title of Il Re, but because he is also the "middleman" to the direct source of Line. Nano leaves suitcases full of vials of Line for Shiki because he, too, wishes to see Line spread through the city for his own reasons. Without Line, Vischio would have never been founded, never mind quickly rise to power as it did.
The scene where Shiki delivers a suitcase of Line to the Palace happens in every major adaption of Togainu no Chi: it is in Shiki’s route in the game, in episode 5 of the anime, and in chapter 3 of the manga.
- "Il Re" is Italian for "The King."
- Though it is pronounced "Il Re" ("イル・レ"), the kanji for "king" ("王") is used when referring to him in the game.
In one of Shiki’s bad endings, he takes over Vischio completely. It is unclear whether or not he continues to use the name of Il Re.