So is it just the wish that made him fall in love ?

in my opinion, that's all it is, and it isn't genuine. Before he had "feelings" for Sein is who he really is, torturing and abusing omegas for sport. He's a rotten bastard to the core who didnt give a single fuck about Sein's emotional or physical well-being. on the contrary, he took pleasure in watching Sein suffer. His "feelings" are just the result of wishes from his bonder

Thank uu so much