Obvious solution 5:
The demon-vampire-marine and demigod can be shipped together. (Not recommended if you want to be paid. But hey, it's an obvious solution.)
Brilliant.
If you decide to scrap the project, do this and insist that they pay you.
You misunderstand. This is exactly what they
want, bizarrely enough. It's a couples commission, one of them is buying it for the other as a gift.
As for money - I'm not concerned, even if they do end up not paying. It's an iron artist situation, where I accept any and all (reasonable) commissions and prioritize normally priced ones (according to my normal rate) over donation-level stories, and donation-level stories over free/non-prepaid. After a certain point, I stop accepting new commissions, and then a certain point after that I refund stories that I haven't gotten to. Rather depressingly, my deadline is fast approaching, and lack of new work has only brought in this one commission - I'll extend the time, but I had hoped for there to be more fire in this trial-by-fire.
This is the only reason I'm worried about it at all - I'm trying to build a reputation as someone that can write intriguing stories given a character or two and a basic premise. Which I can, so long as the premise isn't boring and the characters aren't poop.
The issue here is that their characters are bizarre and overpowered to the point of being uninteresting.
But nope. Romance
Their being Mary Sues doesn't create any more problem than cell phones do. A clever writer doesn't need to rely on faillings as plot devices. Especially since this is, as you say, a romance story.
Oh, I could easily write a story around their characters as they stand. They wouldn't be very nice. Honestly, I can't imagine them liking each other very much, but there you go. You've got immortality (vampire/demigod) combined with practical immutability (teleportation) in very young characters. The result inevitably trends towards making them unsympathetic out-of-touch bastards in need of a good ass-kicking/black-hole. Jumper and Watchmen come to mind. Since they're irredeemable Mary Sues, this probably won't make my commissioner very happy. It's exactly what I'd write (and what I want to write), if it weren't for the fact that they're not my characters and I've already got other projects that I could better focus it on.
I've contacted the commissioner, and I've given him a couple of options. An origin story placed before they gained their powers (and dealing with their meeting to gain them), kicking them off a bridge by making a bigger and badder enemy pursue them, and simply introducing flaws to their concepts to make them more human, amongst other things. I've also mentioned a couple of other writers that might be willing to take on the story instead.
