
Hear me out. And pls don't bash me for this. l'm fine with yaoi okay? We all are. I'm also okay with the whole "I'm a half beast half human shift-shaping thing" I can get behind that. What I find kinda iffy though is the part where he gets fucked by a cat. I ain't down with no bestiality. Maybe that's just meeee.....but yeah.

They're just rubbing there dicks. I think?
Ch. 1
http://www.mangago.zone/read-manga/kemonohito_kareshi_no_dokusenyoku/mdx/d_v-1-chapter-1/22/
Ch.2
http://www.mangago.zone/read-manga/kemonohito_kareshi_no_dokusenyoku/mdx/d_v-1-chapter-2/27/

You need glasses, my girl. In the pages, you can clearly see they're doing it - images of panther x human + image of penetration, after, you have an image where the panther turn in human.
http://iweb7.mangapicgallery.com/r/newpiclink/kemonohito_kareshi_no_dokusenyoku/1/3b885b63b600003dd733e8d7e33c4588.png
Even if the panther didn't really "penetrate", it tried to.
You say that since it's only rubbing, there's not problem?
Do you usually do rubbing with animals? Omg...
In case you don't know, rubbing is still a sexual act.
Not that it justifies his actions, but no wonder Sangwoo is so fucked up. Also kinda explains why he's so bipolar with Bum. He has mixed feelings about his mom and I think he's reflecting those feelings onto Bum cuz they look similar.