Kostya Milkovsky

Kostya holds Kirill in his arms and feeds baby formula from a bottle, watching Kirill greedily swallow the liquid nutrition

this is the omegaverse. Zhenya is an alpha, he is like a fertilizer of both men and women, and Kostya is an omega, he is the weaker sex despite the fact that he is a man. They are a gay couple with a small baby