Kailanne's feed

I really want to pin point why did he slept with the b*tch before? It has been mentioned several times, and I'm getting really confuse on what does he really feels? what does he really want? Is there some hidden intention? ( for some reason, I still don't trust him) what is he after? Like bruh??? Chill Anyways, Nadricka is such a bottom and I live for it