[Crossover] The Whole World Can Hear My BGM

Bu Hai has a superpower called [Everyone in the Room Can Hear My BGM]. The power itself has no offensive capabilities. At most, it plays the appropriate BGM in other people's minds. So Bu Hai, whose ability can't attack anyone, decides to train in hand-to-hand combat with his neighbor, Brother Hibari :) Later, Bu Hai is accidentally hit by the Ten-Year Bazooka and ends up in the Taisho era. After testing things out, he discovers that ordinary people can't hear his BGM, so he lets loose, manually turning up the volume and playing all sorts of hype songs every day. Ordinary people can't hear it anyway, and he can change tracks whenever he's bored. This superpower is actually pretty useful, right? Then, while he's taking a break, a blond boy covers his ears and complains, "Please, I'm begging you, turn it down! My ears are going to explode!!!" Bu Hai: I'm just really aggrieved, jpg 1. It's called the whole world, but actually only certain people can hear the BGM. 2. I'll think about the CP. I seem to have tentatively settled on Zenitsu, but I might change my mind halfway through [Agatsuma warning, jpg]. 3. Thanks for asking, there is no side CP. Theme: Music sounds so good, jpg