Luke has a terrible, deep dark secret : he's got a massive master-slave kink, and he's on the slave end of it. Which is a huge horrible NO NO BAD WRONG DON'T GO THERE when you grew up on Tatooine. (Possibly even worse if he ever learns of his family history.) The fact that he's been calling his teachers 'Master' and has a bunch of kids calling him 'Master' doesn't help with the awkwardness. So he's horribly ashamed of it and has a measure of self-loathing with the whole thing, which he intends to repress forever, good thing Jedi seems to be celibate anyway.

Cue his love interest learning about it and deciding to take it somewhere, telling Luke that it's just a kink and it's okay and it says nothing about them as a person, they'll still always adore/respect him no matter what he wants in bed, PLEASE LET'S FUCK ALREADY, etc, etc.