Mumei is confined in a classroom full of traps. 
Trying to escape along with his comrades, they set off the traps and are sent to another world.
A strange old man was waiting there. 
Mumei's classmates exhaust themselves without skills going up against an enemy that gets stronger the more he drinks.
A sense of foreboding reaches the bewildered Mumei.
I'm not gonna stop until that day!
لن أتوقّف حتّى يحين ذاك اليوم
No me detendré hasta ese momento.
No me detendré hasta ese momento.
Je le libérerai coûte que coûte.
Não vou parar até chegar esse dia!