Someone plz explain the family tree.... I am confused

In South Korea, two men aren’t legally allowed to get married. But they really wanted to be together in a legal way so if they can’t get married and share the last name, Haebom adopted him so he can have Kwon as his last name. So they’re related/family in name only. So yeah, Haebom is technically his adopted dad lol but they did it only so they can have the same last name and symbolically be together that way

So Sungho is an orphan. Sol (the baby) is Sungho's biological daughter, and Kwon Haebom is his romantic partner. They can't get gay married in Korea and there isn't a civil relationship they can enter, so the only way they could legally become a family (which is important for all kinds of legal and medical reasons) is by Haebom adopting Sungho and becoming his father on paper (possible because Sungho is an orphan)