Due to very bizarre circumstances, the human boy, Suzuki Iruma, ends up in the netherworld. He is keeping the fact that he is human a secret and attends the Demon School Babyls. Because he is human, he cannot use magic so he had been using the Gluttonous Feeder Ring to get by in school. But then one day, the ring started to speak! Why, though? Iruma then meets the incarnation of the ring who calls themselves Alicred, AKA Ali-san.
Who's there?! Don't use vacant 
rooms without permission!
!من هناك؟! لا تستخدم الغرف الشّاغرة دون إذن
Wer ist da? Hier werden nicht einfach
offene Räume benutzt!
¿Quién está usando esta sala
sin permiso?
¿Quién está usando esta sala
sin permiso?
Qui va là ?
Cette pièce est interdite d’accès !
Chi c'è qua dentro?! 
Non usate le aule vuote senza permesso!
Quem está aí? Não use
salas vazias sem permissão!