Yui is a big fan of Girls Dead Monster who is also acting as an assistant for publicity and other matters. She became the lead vocalist after Masami Iwasawa disappeared. She had sung "Thousand Enemies" as a lead vocalist while the other song, "Shine Days", was not fully sung in the series, but only its chorus. Her singing voice is LiSA. She's one of the heroines of Angel Beats! -1st beat-. Yui has long, pink hair and hot magenta eyes. Her hair is two bunches tied up with dark red laces and two twintails on the sides of her face. They are held together by small cross-shaped barrettes. She wears the same uniform as Yuri Nakamura and the other girls, although her shirt appears to be small enough to see her tummy. She wears crossed black ribbons up to her knees and black boots. Though they don't seem to be in use, she also wears garters on each thigh with the addition of black choker around her neck. On her wrists, she sports single handcuffs with few slabs remaining on each (possibly, both parts formed a common pair of handcuffs). She wears wings that are hidden behind her hair. Another particular trait of her is her "demon tail" which seems to twitch and move whenever she is excited, happy, or emotional in any way. She also has two pointy teeth like a cat. Yui is an extremely bright, cheerful, crazy and wild girl who is known to be hyperactive and talks extremely fast. Even within the members of the SSS, she comes off as very excited and loud. She is often flirtatious with others, and takes advantage of every opportunity she can. She usually tells the other SSS members that they're "morons", mostly because under the surface she is actually quite intelligent. She is also a huge admirer of Hisako because of her 'murderous' guitar rift. Her upbeat personality is most likely inspired by her past life in the living world where she was paralyzed since she was four years old from head to toe.