He's being kept "like" an omega by another alpha. So no he hasn't changed. kiwikitsune
I felt sad for yuki. I think he became a "kept" alpha because of his incident with little brother. In a way, his life is ruin by that incident. He also couldnt overcome the guilt he felt for impregnanting his brother.
I didn't get what happend With yuki, the brother. He was an alfha and then became an omega.? (⊙…⊙ )