Considering that everyone is so open minded to *ahem* erotic fantasies of sibling foursomes I'm going to have to accept the characters. For your intros you will be joining my class. Mutou is so damn scatter brained he likely forgot your arrival. 

Groups will be split as follows. 
Kyle Parker
Tomohina Mizukimura
Sibling number bro

Fuyuki Todoroki
Shiori Hanari
Sibling number sis

Forgive me for not knowing your names yet, I'm writing this all out on my phone and can't swap pages while writing. But yea I'll give you temporary npc mastery over mutou for your intro post. Unless you want me to do it which won't be until much later. 
Back to work.