Pls help find

Hi! Looking for a manage I read ages ago.
It’s bl and omegaverse.
It’s about an omega who is now a single father. The father is an alpha from his past, I think they met in college of high school, in America. But the mc flew back to Korea and is now working in his friends restaurant. The problem begins when mc encounters again, years later, alpha as a customer at the restaurant.
The alpha is really rich and going to inherit a pharma company. He and his son have this rare genetic disease only his family inherits due to being dominant alphas or so and mc can’t afford the expensive treatment for his baby, so ends up accepting alpha’s help.
Alpha secretly sacrifices himself so that his father can experiment with him and the father is actually the villain and pisses me off