Character development doesn't inherently have to come from romance, and there are lots of other kinds of "something else" you could write other than romance for readers to connect with, even other kinds of dynamics, like friendship and siblings.
My MC Alicia's love interest is her best friend Kattar Moon. His mother is the person who helped Alicia start her company and become a successful artist. He himself is a stunt driver, until he's paralyzed in a car accident driving her home one night when she was less than sober.
In "Rigamarole" the love interests aren't really the focus because the story is about the dynamic between the two siblings Leia and Riley. But Leia has two crushes. One is her BFF Ryan, the other is the son of one of her dad's friends.
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