Mob Choir is the name of a Japanese musical project specially created for the anime "Mob Psycho 100". The main vocalist is Sana (also known as "37", may 25th, 1999), a Japanese singer member of the band Sajou no Hana. "99" was composed by Junichi Sasaki and Takeshi Masuda and played (guitars and bass) by Masuda. The lyricists were Sasaki and ONE. "99.9", on the other hand, was performed by Sajou no Hana.