First of all Igawa if you're gonna do something like cheat break up with his sister first ...

While I agree with you, I do not like the cheat and wish for no cheating, but I do want the sister to learn a lesson and get hurt a little in some other way. Cuz it seems like she's a 2 face and selfish and sometimes sneaky, and has made life hard for the uke. I think there is even more to the relationship with the sister and uke than we see in just this chapter.