Ever since he had met Bruce, Schiller had believed for a long time that Bruce wanted to become Batman because, on the night his parents died, he had seen bats flying through the dark attic. The fear lingering in his heart had made him see bats as the embodiment of fear, and once he became a bat himself, he could bring that fear to Gotham's criminals.
But after Bruce graduated, Schiller realized there had not been nearly so many twists and turns involved, nor did bats possess any special meaning—Bruce simply liked bats.
It was only afterward that Schiller learned Bruce had always wanted to keep bats at Wayne Manor, but Alfred had disagreed. Aside from the diseases they might carry, their droppings were simply too troublesome to clean up. It was one of the few things Alfred would refuse Bruce.
After the inner world came into existence, Bruce finally fulfilled his dream of keeping bats. After all, the buildings here were constructed through magic and had self-cleaning functions, and no one here was afraid of bat-borne diseases.
Moreover, because mages often needed to brew potions and draw magic arrays, bats could be considered traditionally raised animals in the magical world. There were fairly mature selectively bred varieties, stable methods of husbandry, and specialized workers. So Bruce funded the reconstruction of Oblivion Bar, while Night Master found him a group of dark elves from Maia in the magical world to raise the bats.
Perhaps because of some unusual disturbance, every naturally occurring urban animal in Gotham had an uncanny talent for magic—and understood it a little too thoroughly.
After producing magical spider spirits two stories tall, enchanted stray cats that grew eight tails, stray dogs that transformed into the Werewolf King under the full moon, and magical sparrow demons with