Aquamarine Hoshino (more commonly referred to as “Aqua”) is the main protagonist of Oshi no Ko. Before the tragedy that struck his family, Aqua was considered relatively normal other than his unparalleled prodigious talent in acting his quick wit and intelligence. After the tragedy that killed his mom, Ai, he changed, becoming cold, calculated, cunning, and discreet, he would do anything to find the man who killed his mom. Aqua is described as someone with emotional distance. He’s an actor.