Because the FL's mother left him (without telling him she was pregnant). Time went by, but he was pressured into marriage. He's the emperor so he needs to have an heir and at this point he figured the woman he loved was never going to come back. He ended up with the empress who was in a similar situation as him because she was in love with another man, but her father (duke Flyod or whatever the title) had him murdered. So anyway their marriage was just of convenience.
The emperor may not love FL's mother anymore either, since she did hurt him deeply in the past and it's been a really long time (we don't know how long, but at least 11 years).
Makes sense, but it is odd that he ended up having two kids
Fl is an elf, she is the oldest so there is no cheating involved
I just started reading the story, but I don’t mind spoilers? How come the emperor ended up having two kids with the emperor when he loved the female leads mother, and then proceed to have another child with the Empress? Are those his biological children or it’s just one of those once again man can sleep with two different women situation? Even if he loves one and doesn’t love the other.