Rampion by Susan Trombley

Sometimes, you find love in an unexpected place…

Rapunzel isn’t fond of being a princess, but her rebellion against her royal parents can only take her so far. When her adventures playing pirate result in embarrassment for her family, she’s sent away to a scrapyard in the middle of Nowhere on a barren moon that has been barely terra-formed to support life. As far as Zel can see, the only other person on the moon is a grumpy old caretaker named Gothel, who doesn’t bother to show any respect for her royal status.
Old man Gothel has plenty of rules, and he’s made one huge part of the scrapyard forbidden, which means Zel can’t resist exploring it. In that forbidden area, she discovers a tower, drawn there by a sexy, masculine voice singing unusual music.
But when she finally finds her way inside the tower, she discovers something she never expected.
There’s a lot more than just a heart on the line when it comes to the secrets that surround Rampion and his captor, Gothel.
Rapunzel must learn the truth before it’s too late and she loses everything she holds dear.