Gin-san takes history lessons, and teaches you how to hide your porn mags?
Tsukuyo tries to teach Seita history, the subject he's not great at. However, her training (?) methods end up leaving him scarred, which makes desperate Seita ask Gin-san to take over as his tutor...
But wait.
...لكن
Pero ¿qué pasaría si abrieran el cajón 
que oculta las revistas?
Mas calma.