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...
This room is a fortress to protect porn mags.
هذه الغرفة حصن مخصّص لحماية المجلّات الفاضحة
Este cuarto será una fortaleza.
Este quarto é uma fortaleza para 
proteger mulher pelada.