source: wikipedia
At a young age, Eikichi was overweight and frequently bullied. After a thug pulled down Eikichi's pants in front of his childhood crush Miyabi Hanakouji, he underwent a radical image makeover, losing weight and training to beat up anyone who mocked him. Eikichi was capable of summoning his own Persona before Tatsuya and Lisa. Like Maya and Eriko, he misunderstood the phenomenon and dubbed his Persona a "Spirit of Death", which he used to punish anyone who challenged him. This acquired him the nickname "Captain Death" — parodied by Lisa Silverman as "Captain Underwear" — and resulted in Eikichi becoming greatly feared and admired within Kasugayama High School. He is a true narcissist, always looking at his hand mirror and praising his own reflection.
Eikichi is also the lead singer of a rock band called Gas Chamber, whose logo he wears on his armband. The group consists of Eikichi and three of his friends Shogo, Ken and Takeshi. Eikichi insists that people address him by his stage name, "Michel" (a stylish name that sounds closest to his surname). Though none of his three friends can play instruments well enough, Eikichi believes that the band will achieve fame through his vocals alone. They have composed one song, entitled "Luv Beam".
Eikichi often wears makeup and dresses like a visual kei rock star despite the impending fear that his traditionalist father Kankichi would punish him if he knew. He wears a modified version of Kasugayama High's blue uniform, with a tunic over his pants.
Though outwardly self-centered and cocky, Eikichi takes his role as the school leader very seriously, and actively looks out for the welfare of his friends and classmates.