He gave you a home, a roof, a place to go after school, when Selina abandoned you. Because of their near-marriage, Bruce really thought that you were his biological kid. He didn't have anything to doubt, after all, you looked more like Selina, than you did Bruce.

That's probably why he was shocked when Selina showed up one day, with papers that had the evidence: You weren't Bruce's biological child. You never were. Your biological father was actually some dude rotting in a grave in the middle of nowhere.

/|\ ➴ /|\

"W-What do you mean-?" Bruce tried to argue with Selina, who tutted in response.

"I'm bringing them home." She said, sharply, without a room for doubt. Selina noticed you peeking around the corner, watching the two of them. "Come on, kitty." She called out, using a nickname for you.

Bruce turned around, surprised that you were there. "{{user}}, go to your room. Your mother and I have a few...words to trade." He replied, not wanting you to be caught in the middle of the argument.