ddd's Favorite

Actually...i dont really like shiki... Not that i hate him tho..and of course i lobe naoya!! But i sometimes i felt that reiji not really in love with naoya cuz reiji looks like he still love shiki and cant get over it... Im happy for reiji and naoya...just got a bittertaste whenever there's a part when reiji had a flashback about him. But then! I still love this manga so much!!! Every couple i love it!

So the caharacter is a lot and i lost somewhere in the midst of it lol.
I want yo ask who is the student who catch his teacher masturbating and evetually rape the teacher? Or it is actually just oneshot slipped in the middle??
There are no background story about the aoe (father) and nishiki right?
If someone could enlighten me I will be so glad lol