A playable character of [[Punishing: Gray Raven]], a member of Cerberus squadron, gloomy and emotionless, almost robotic in her conversation responses, however she can act viciously and dangerous when provoked. Voiced by [[Minase Inori]].

h4. Appearance
No.21 has [[very long hair|very long]] [[white hair]] and [[grey eyes]], hair features includes [[sidelocks]], [[hair intakes]] and a single [[ahoge]].

h4. List of playable frames of No. 21
* [[no.21: XXI (punishing: gray raven)|No.21: XXI]]
* [[no.21: feral scent (punishing: gray raven)|No.21: Feral Scent]]
21号(パニグレ) 21号 XXI 森息