Yes, Qrom will be romanceable and I'm hoping to add at least one more character to be romanceable as well (just haven't decided on the details of that character yet).
Currently since I didn't have actual art assets for Qrom or the fifth character I left the two classes relating to those two unclickable. In future updates, if the option isn't available yet I'll add a note in game.
While each class will have a romanceable character tied to it, you will still be able to romance any character regardless of the class you choose. It's just that starting out I was waiting till I had more assets for the characters relating to those unselectable classes.