Not an Inferior Little O? How Did You Become the Boss's Favorite?

[Two male protagonists + ABO + double cleanliness + marriage first, love later + doting on wife + 1v1 + he] A double-standard father with a bad mouth is a master of attack vs. A gentle, clingy, tough, sick, and beautiful woman. Si Mian is sweet and beautiful, and her long pink hair makes people unable to take their eyes away. Unfortunately, she is a sickly boy who gasps every three steps and coughs every five steps, and is also a low-quality omega. After accidentally discovering that his stepmother was inciting his father to sell him to the powerful in exchange for money and power, Si Mian ran away overnight in order to prevent them from becoming the plaything of the powerful. But unexpectedly, he was knocked unconscious and sent to the bed of Feng Yanhan, the living king of hell, and almost died (didn't do it) After waking up, he looked at the marriage agreement and the note in his hand. The cold and exciting conditions, he signed his name without thinking. Omega originally thought that this was just a deal where everyone gets what they need. As long as they play the role of the housekeeper and wife, the marriage will be dissolved when the agreement expires. Later, before the one-year deadline was up, Si Mian was informed by Feng Yanhan that the agreed marriage was cancelled, and the man in front of him had already turned red in the eyes, and his tone was extremely low, "Baby, can we not get divorced?" Si Mian was confused. It turned out that he was not the only one who was emotional in this "transaction"... — — — — Feng Yanhan, a cold-blooded and ruthless King of Hell, thought he was destined to die alone in his life, but an accident disrupted his peaceful life. From then on, the dead trees became spring again, the broken branches turned green again, and Feng Yanhan's world welcomed his little sun. [Demining: There will be a little baby in the extra story, and there will be multiple pairs of sub-CPs (there are very few scenes in the main text)]