Girls Dead Monster is an all-girls band made of students from the afterlife school. Also known to their fans as GirlDeMo, it is a sub-division and affiliation of the SSS, cooperating in certain operations.
It is formerly led by lead vocalist Iwasawa. But, after Iwasawa's disappearance, Yui become the lead vocalist. But since she has disappeared as well, the current vocalist is still unknown. The other members had disappeared when they revealed that there is no one will replace Iwasawa and Yui as the lead vocalist of the band.