I'll try to make it short.
It was a shoujo/josei manga, but I'm sure it fell under comedy genre as well. The FL (light hair) and ML (dark hair) got married, but it was a loveless one. FL fell for him first, and he fell for her later on. The ML grew up in an orphanage, and there's two side characters that are friends of his: One's a girl he grew up with, she has burn scars, and is in love with ML. Another is a guy friend of ML, he gives off mafia vibes, he's a womanizer and an asshole that hates the FL and loathed their relationship, he even tried to force the FL into sleeping with him, but she ended up giving him a hj It's a dark comedy.
Two other side characters are a girl and her doctor who she fell for. They got together later on, but he treated her bad, until he confessed that he was insecure of their age gap. There's also FL's boss? I think he got injured trying to save his son, or something like that...