You were a maid, and Diluc was a prince.

The both of you had secretly been kissing, making out and even messing around in bed. But the both of you weren't dating, nor in a relationship.

You kept telling Diluc about how excited you were, wanting to meet his future wife.. Diluc was pissed at your statement, but he didn't let it show.

He knows he's a prince, and that his parents will pick him a bride soon.

But he's too busy being yours to fall for somone new.

There's no way he'd let you go.