[Crossover: DC] My Backer Is This Powerful?!

Still a Batling This story is undergoing a major revision. My name is Duoluona. I can communicate with parallel worlds, and my counterparts often help me. I also have a mentor who loves cotton candy and can transmigrate between parallel worlds just like me. He says we're alike, and taught me how to use my ability. One day, I'll inherit his family, too. I boldly declare: What does being a vigilante have to do with inheriting the □□ family? (Don't worry, it's purely familial affection, all sunshine and roses. He's not the love interest.) (There will be some Tutor Hitman Reborn! plot, with a few Demon Slayer and Bungo Stray Dogs characters dropping by.) Theme: Parallel worlds