There's a book written from the perspective of a mini person in a relationship with a poly partner: Mono in a poly world. It's a short interesting read. *Spoiler alert: in the end, they decide to go their separate ways, so it's not a purely "happy ending" story. But it's also open and accepting, not for or against mono/poly relationships, just telling it from the perspective of the mono person, particular challenges and learning experiences.
I recently discovered that https://www.amazon.com/Mono-Poly-World-Partner-Polyamorous-ebook/dp/B08W425KTT but havent read more than 20 pages into it yet
The book Mono in a poly world is an interesting (albeit short) read. It's about mono/poly relationships from the perspective of the mono partner.