Due to some contrived circumstances (maybe some sort of curse or obtaining some type of inheritable title), Jester needs to have a child with a tiefling father. Since she doesn’t know any suitable candidates, Beau offers to transform back into her male tiefling form.

I’m okay with Beau and Jester being in some sort of established relationship (though I would slightly prefer if they weren’t), but if they are, I’d like it to still be a situation where they hadn’t planned on having a child (at least not in the short term) and hadn’t been planning this.