They must've hooked up and one of them has internalized homophobia, which I believe would be Hyoseo's dad. Maybe during their studies, the current CEO used his sperm to create a human orca, Haeil, but he doesn't instinctively treat Haeil as his own child cause he's cold and calculative. Like he only created him as an experiment, not to actually be a father. I mean they literally look similar. Or maybe he is also a human orca. I'm just making up bs assumptions. There hasn't been anything to based these off of and we're already at 49 chapters. I think the author should've started releasing some info earlier tbh

What is up with the daddies? They so sketchy