Juyu's manga / #neighbours(3)

Childhood friends Ginu and Yubin live in separate apartments in separate buildings right next to each other - so close, in fact, they can talk to each other and see into each other's apartments through their windows. But Yubin's long-held secret is revealed one day when Ginu sees him doing something naughty through the window...

A guy accidentally witnesses his friend masturbating. This shouldn't really affect their relationship any, right? After all, men see such things all the time; it's just an amusing incident, to be laughed over once the embarrassment has worn off. Or maybe...