Okay I know we all love the headcanon that Danny becomes the King of the Infinite Realms after defeating Pariah Dark in a 'Keep what you kill' kind of way, only its not kill but defeat in combat, but what if Danny's future consort/husband/wife is chosen the same way.
Like what if Danny is dating one of the Bats (can be anyone tbh from any fandom, I just love the batfam) and they've been dating in secret for a while and knows each other's identities. The one he's dating even knows about the King thing as well, that's how much Danny trusts them at this point.
So when they wake up to a glowing green sticky note with the words 'Alls fair in love and war. -CW' they know of the ghost Clockwork and his riddles ways, and keep on hand the anti-ghost weapon (in their preferred weapon of choice) Danny had gifted them as a 'just in case' option, all day.
So they were fully prepared for a fight when they, and the rest of the Batfam, get pulled away from their dinner to the Infinite Realms, in a huge castle in front of an empty throne, surrounded by a bunch of weird eyeball ghosts and one angry/jealous, snobby looking ghost, whose been trying to gain Danny's eyes/favor for months now especially since they have the backing of the Observants but nothing works, and said ghost challenges the "Current lover of King Phantom to a duel for the rights of courting him!"
(This law was created by Pariah Dark who wanted his future consort strong so he let them fight it out for the spot. It was entertaining for him to watch ghosts fight for it. But it needed to be done in front of the throne, no King was needed to be present, and both fighters needed to be endorsed by powerful and old beings (the ghost fighting for Danny's hand had the Observants, meanwhile the bat Danny is dating had technically been endorsed by Clockwork when he sent the sticky note)
They fight, the Bat Danny is dating wins, and Danny returns from a 'oh so serious problem' the Observants said he needed to fix only to find the person he's dating in an argument with Clockwork over 'I only fought because Danny isn't some prize anyone can claim, we are not forcing him to stay with me even though I won. He has the right for his future.', Clockwork whose just smiling and chuckling in his all knowing way, the Observants tied up in ghost rope, the annoying as heck ghost that's been trying to get in his pants for the last few months also tied up and beaten up, and... oh boy that's the Batfam... all watching... and yep they're all looking at him.
Not the way he wanted to finally meet them.
