SPOILER
So let me guess this right... after he thought Young was killed by the queen, he went crazy and killed both the crown prince and the queen, he replaces the prince, lives by the prince’s identity and makes a deal with the crown princess (crown prince’s poor wife) that he would make her the queen but just after that, he was revealed that Young is still alive, he went to meet her, brought her back as a guest, kinda trap her in a beautiful palace and they live happily without a wedding and she will always remain an unknown guest and not his wife for the rest of her life...
I like WHAT?????
https://www.manga-raw.club/reader/en/a-kind-goblin-s-bird-chapter-29-eng-li/