Jess Buck
HELLA QUEER
Idea #1: Arranged Marriage - Character A is royalty (heir or not doesn't matter) and they're being arranged to marry a foreign prince/princess in order to keep peace between nations. A is already secretly involved with B and doesn't want to get married. B can be anything really but my initial thoughts are that they work at the palace so there's an added layer of class difference as well as a queer relationship.
Idea #2: Royal Polycule - This one would obviously be a 1x1x1 but the basic idea is that Character A and Character B are betrothed, literally getting married in a couple of weeks. When all of a sudden Character C shows up and somehow sweeps the both of them off their feet. This idea is less fleshed out than my first one so I'm open to any ideas that you may have.
You can let me know here if you're interested or shoot me a DM. Either way I'd love to hear from you!