This is where the Dark Knight raises your Sonic OC or a Sonic character. (Let me know if you want yours to be Marvel instead)

Scenario 1: Your parents were killed off by (insert Batman villain here) while you were a baby/kid. Batman found you and later adopted you from the orphanage as Bruce Wayne. How will you react when you find out your adopted dad is secretly Batman?

Scenario 2: Your parents left you behind on Wayne Manor's doorstep, where Bruce Wayne found you.

Scenario 3: (this scenario is if you want Batman to be Mobian) Batman and (female character) had a kid together, you. Years later, Bruce worries you might be trying to follow in his footsteps as the next Bat of Gotham. Are you determined to be the next Dark Knight?

Scenario 4: Make it up