@ChildofBears
It's okay if your not into UnderTale anymore. Everyone has different fandoms to switch on, but would still love what fandom they we're!
You can rewrite the book if you want since it's yours. Or probably make another book for a rewrite cause some fans still loved that book (including me)
Take all your time and motivations to get back, since we might still be waiting, but if you really can't go back and stay on your new fandom, it's alright! Just remember to be still nice, respectful and ship your ships to your fandom!
No need to over worry about something you don't want to be bothered anymore, maybe just a little keep in touch too ^^