Res ipsa loquitur

Actually I think soulmarks have been pretty well explored for romance -- but not in any way that I like very much. What if we tried: 

- "It doesn't mean I like you. It means it's my life's task to learn to be allies with you."

- Soulmarks were only really for peacemaking royal marriages, and they've been unknown since monarchy stopped being a valid system of government. So when that mark shows up on your arm, what the hell do you do? 

- It turns out that the marks are the result of a third party, an alien intelligence, and this is how it's participating. Basically you are both Xorg's lovers now.

- The marks don't match one person with another person but sort people into groups. You don't have a single soulmate, but you do know you're looking for someone with a diamond on their shoulder.

- That scenario where you share what your soulmate experiences -- you just conclude that your house is haunted.

- Person A: I found my soulmate and I'm intensely attracted to him and tenderly interested in his wellbeing but tbh I don't respect him or even especially like him. Person B: I found my soulmate, but I've been playing this role for so long I don't know how to show him who I really am

- "So this means I can't be with anybody else as long as you live, right? Guess I have to kill you."

These days I'm reading a lot of Witcher, which has tons of delightful nonmonogamy, and Cobra Kai, which has a wife cool enough that sometimes writers keep her around instead of AUing her into a beloved ex-wife. So I have pairing-plus romance scenarios on the brain.

- We got together very young, and I was your first everything, and sometimes I worry that you'll feel that you missed out. You're willing to indulge me by sleeping with other people.

- Variation: You're hypothetically willing to indulge me, but there's nobody in particular that you're interested in. But you're aware that there's someone I'm extremely interested in, even though I'm trying to hide my crush. And that's the person you propose.

- You and I had a casual FWB relationship, but you and he are a love match. When you invited me back to fulfill a fantasy, of course I said yes: I know some secret tricks that work really well on you, and I thought it would be fun to teach him how to do them.

- Or, same as above, but I said yes because I have to make sure he's worthy of you.

- You take care of me. Oh, boy, do you ever take care of me. I'd like to watch somebody take care of you.

- You made the suggestion to me, but you're obviously way out of my league; I don't understand how this is not obvious to you. I have an occasional fun partner who's much more on your level. Maybe I can get the two of you together and then just fade back and leave you to it.

- Been a while since we brought in another partner. You sure you wouldn't like to ease back in with somebody a little less complicated?

- We invited you into our bed, and it was good. And then the next time we saw you, you had slid into the role of Our Rough Trade, Our Bit On the Side, Our Midlife Crisis. You were diminished. It's unbearable.

Here's another thing that's all very well for porn but has missed opportunities for romance: the a/b/o worldbuilding trope where the alpha penis sometimes has a knot on it, sometimes resulting in two lovers being tied together for a long period of time. The stories I've read have sometimes mentioned this beforehand, in anticipation or dread -- "and then we'll be attached together for the thirty-minute alpha orgasm" -- but when they actually get there, we usually get a few minutes of conversation or dozing followed by a fade to black.

OK, my first thought about this is actually more porn, namely: I want better descriptions of what it's supposed to feel like to have an orgasm that lasts half an hour. (Who was the comedian in the eighties who said, "My mother was in labor with me for 36 hours. I don't even want to do something that feels good for 36 hours"?)

But on the romance side:

- We can just about keep the awkwardness at bay for long enough to have sex, if we do it so fast and intense that nobody has a chance to say something they can't take back. We definitely can't keep the awkwardness at bay while being unbreakably attached to each other for half an hour.

- Now you're attached to me for thirty minutes, and also somewhat debilitated by pleasure, so I think this would be a great time to ask you that question that you always avoid answering.

- Now I'm attached to you for thirty minutes, and also somewhat debilitated by pleasure, and my ability to pretend that this is just meaningless sex is being severely tried.

- I've had bad luck with prior relationships, and my experience of this thirty minutes has been really godawful. I don't know what it's like to experience this with someone I can actually trust.

- I have to make sure this doesn't happen with us; I owe it to you to make sure you can always make a fast getaway and not be stuck with me for half an hour, because nobody would want that.

- Actually I can do it with you. I just have to make sure we're in a position where you can't see my face while it's happening.

- Holy shit, I've never had anybody talk dirty to me for the entire thirty minutes. Uh, that makes it forty-five minutes. My mind is blown.