When he was a child, he was called "brother" when he grew up. During the period when he was fostered in the Gu family, Xia Zhufan met a little tsundere brother. This little tsundere was unwilling to tell him his name, so he didn't even know his name when he left.
When he grew up, a little crush suddenly appeared next to him. Whenever the other person called him brother, Xia Zhufan always had a familiar feeling. It was not that he had no doubts, but he was always interrupted by the black belly.
By the time he reacted it was already too late.
Intention: Reunion after a long absence