Asa is Narumi's closest person and a huge admirer. He's got it quite hard in the prison. In his first day in the prison, he witnessed something he shouldn't, so he got his tongue cut. Riki Oh and Asa got close after the fight with Narumi, and Riki Oh gave him his flute. Despite his childlike look, he's probably a midget, since he's in a prison after all.