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...
It's another name for the Onin War, dumbass.
اسم بديل لحرب أونين أيّها المغفّل
Otro nombre para la Guerra de Onin, torpe.
É outro nome para a 
Guerra Onin, seu imbecil.