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 way, she'll be so happy, she'll 
forget all about finding the porn mags.
ستعترمها السعادة على هذا النحو وستتناسى أمر عثورها على المجلّات الفاضحة
Estará tan feliz que olvidará 
buscar las revistas.
Assim, ela vai ficar tão feliz que
 nem vai lembrar o que achou.