Akechi, Gorou

Akechi is a high school student who conducts a detective business. His abilities as a detective have been widely acclaimed, since he not only has solved numerous cases, but is also able to deal with people from the investigation agency smoothly. His handsome features draw him public attention, and people comment on him as "The Second Advent of the Detective Prince."

[Spoiler] He awakens to his persona, Robin Hood, sometime during Okumura's palace. [/Spoiler]

[Spoiler] In reality this persona is nothing more than just that, and he is the culprit behind the mental shutdowns as well as the traitor who turned in Ren/Akira/Joker to the police. [/Spoiler]

[Spoiler] He failed to kill Joker inside a police questioning room, following the orders of Shido [/Spoiler]

[Spoiler] He is Mayoshi Shido's son out of wedlock [/Spoiler]

[Spoiler] He is killed after engaging the Phantom Thieves in combat inside of Shido's Palace. He sacricfices himself in order to let the Thieves flee; he is shot by Shido's cognition of him. [/Spoiler]

[Spoiler] In Royal on December24th, he shows up to greet Joker and Sae, telling them that he'll turn himself in instead of Joker. He is released on January 1st and teams up with Joker, Yoshizawa, and the Thieves to find out what's going on. [/Spoiler]

[Spoiler] At this point, he risks his own life in order to destroy the fabricated reality that Maruki has created, despite the fact that he'll be dead if they return to the original reality [/Spoiler]

[Spoiler] He is suspected to be alive, as someone wearing his clothes is shown walking by the train in the true ending of Royal [/Spoiler]

(Source: Megami Tensei Wiki)