Responses
It seems like he's probably reaching out for something he doesn't have in his home life, considering he doesn't get any affection from his parents. This guy never truly ignores him like they do, so now he isn't lonely. Kurose always has to take care of himself so he's also probably trying to/is growing up too fast.
It troubled me... :/
I don't understand why he would do that.
Yes, he hasn't got affection but, but, mmm... where did he get the idea of licking a person's chest?
That's a bit extreme for a kid, right?