He should just finish the story in novel form and let the anime handle the rest.
Oh okay. Hmm let’s see….. I’ll go with Emitter - I can emit sound (might be through some device that I’m carrying cuz i suck at singing myself or play any instruments) which can make them forget their favourite genre of music and start liking K-pop. Ofc there are some time restrictions but I haven’t really fleshed it out.