The truth is that Batman- Bruce- is completely, 100%, nonrefundable- human.
The problem is that his children, the delights he keeps picking up off the street- are not
Bruce is human, but for some reason he keeps getting trapped in those eldrich "i will give you my firstborn child as a reward" types of things with beings that aren't
Dick was first offered to him by a tree nymph, as thanks for saving her home. He politely declined, but the little fucker followed him home and now has a permanent nest on Bruce's left shoulder
Jason was promised to him by a literal demon after Hal Jordan accidentally summoned one in the Watchtower(they're still not entirely sure how, he was trying to make chili) and Bruce convinced the other League members to stand down and let the demon leave in peace(he'd been chillin before Hal had fucked up and yanked him into space- he didn't wanna be there either) Bruce didn't even dare to argue, just graciously accepted the small burning inferno child the demon gave him and cradled it to his chest(somehow it didn't burn him)
Tim drifted to him in a bottle, his mother a river elf promising him to whomever found the bottle. Tim imprinted on him immediately and just lives on his right shoulder and sometimes front pocket
Stephanie's mother swam up to him in Gotham harbor, gasping for air because the water was so foul and he helped her give birth. Because she'd been born in the literal fuckin asshole of the earth she wasn't able to return to the normal water of anywhere else, so she was gifted to Bruce as thanks for helping her mother get out of the water
Cassandra is a shadow phantom who basically swore herself to him when she found him. Bruce cannot get out of the contract he somehow (did not) agreed to and just accepts the fact that he has another daughter now
Damian was dropped on his doorstep by Talia, a witch. He's just a witch. Idk what else to say.
Duke was given to him by a selkie mother who'd lost her pelt and he had returned it. She'd given him her son's coat so he could own him, but Bruce had been horrified and promptly given it back to Duke. But the fucker wouldn't leave- he's like that penguin or seal or wtv that was released into the wild and then returned 30 minutes later
Anyway yea just Bruce and his fucking zoo of fantastical children. The Justice League meets him and are like "hell yea yup he is a demon creature born of the shadows" when in reality he's just a Tired Dad
Dick appears and flies around Wonder Woman's head, giggling as he makes flowers bloom in her hair and Bruce just sighs. The justice league is like... okay opposite vibe of what we expected but bet
Then Jason appears, fucking burning with hellfire as hair and now they're really perplexed until Bruce says "adopted" but does that mean he isnt a demon? Or is Dick adopted?? Or???
Tim shows up and they're like- okay two kinda fairy like creatures, yea yea. Batman is a fairy, Jason's adopted okay. Bet.
Then Cass shows up and they're like "nope! We were wrong!"
Stephanie gets carted up in an inflatable swimming pool and they have officially lost the plot. Hal flips the table in outrage.
Duke appears and they just give up.