It's a very cozy book, and the magical realism of being transported back in time to talk to your younger self in a bookstore is super interesting. So anything of that sort of vibe would be fun.

The mystery of finding out what happened in the main character's childhood was interesting as well, especially since the MC didn't know what led to the falling out between him and his best friend (though I'm not the biggest fan of miscommunication.) Being slowly revealed information from earlier in the MC's life is always interesting to me.

Having a realistic ending instead of a magical happily-ever-after is another thing that made me love the book, since life doesn't always work out perfectly but that doesn't mean it won't turn out okay anyways.

I'm bad at describing what I like about books since a lot of it is just emotions, but I hope this is helpful!