The Joker is awfully domestic, in his way. He makes pretty clothes. Nathan's perfectly happy to be a clothes horse for his sartorially-inclined mate. Some of the clothes are distinctly feminine, and Nathan does not wear those, although the Joker could probably talk him into a kilt, even if that's not a Manx thing but only their neighbors.
"Well, this isn't the first accidental half-vampire of all time," snorts Nathan.
"...Aww, man," she says, "if we have a kid there's no way we can keep having this much sex, is there."
"They do sleep," he points out. "But this much? No, not really, not unless we follow the Coven around and hand it off to babysitters many times a day."
"Mm, but kids grow up," she muses. "Pretty quick, too, if they're half-vampires. And then we can go back to fucking all the time, if we want."
"That is true," agrees Nathan, nuzzling her throat.
"And we can fuck all we want now," she murmurs.
Yep.
"I think I'll make myself all tasty again," the Joker decides. "That was fun."
"Er," says Nathan. "As long as you're still pregnant and haven't decided not to have the baby, do make sure I'm not taking stuff it needs?"
"All right then," he says, pressing his teeth to her neck.
Nathan growls and sets about developing another bellyache.
"I love you," she says, when he is finally done chewing on her and the wound in her neck has near-instantaneously disappeared. "I love you lots."
"I love you," he says in a half purr, half groan. "And how you taste when you do that."
A few days later, there is a knock on their door.
Nathan's been too preoccupied to be checking his timer for things like "correct times to get dressed", so he calls, "Just a second!"
The Joker snaps her fingers, and they are both abruptly dressed—her in a proportions-adjusted version of the white dress that started all this, him in that blood-red shirt he looks so beautiful in and a pair of black pants she made him later.
"Thanks, babe," says Nathan, and he gets the door.
It's Bella. "Hello ag-" She stops mid-word, peering at the Joker.
"She turned herself into a woman, we didn't think through the consequences of that, a few hours later she wanted French toast and I guessed, at this point we are pretty sure, she hasn't decided yet about having it but leaning towards yes," Nathan summarizes.