Immortality. Life without death. This is something many people seek. But suppose they were to find it. Without death as a deterrent, what would hold back people, if their conscience proved to not be enough?
In this plot idea, our characters would be a pair of what are known as Valkyries. They aren't actually Valkyries in the Norse sense. However, they are as immortal as those Valkyries of myth. However, they still have human tastes, human impulses, human pleasures...in all terms except their mortality, these Valkyries are human.
That difference is a problem, however. Mortals have concerns with these Valkyries, concerns that they might act as vengeful or cruel gods. For this reason, the Valkyries are kept in certain sections of the city of Benai. They are strongly encouraged to keep to themselves, and some Valkyries don't like that. For this reason, certain Valkyries that have proven themselves are tasked as enforcers. They keep the others in line, through any means necessary.
In essence, our characters would be a pair of Valkyries, left to mingle among their own. The issue is, at least one of the Valkyries is rather twisted, and with those dark inclinations, being surrounded by beings that can handle anything done to them is a dangerous situation. At least, for the others.
As you can guess, my character will not be one of the moral Valkyries. If you decide to follow along those lines of immorality, our characters would be a team, having fun with victims that can handle anything. If, on the other hand, your character is of moral standing...well, that would be a bit of a conflict, wouldn't it?
Now, an important thing to define is "immortality", and how it works in this RP. Basically, it's not so much that Valkyries are immune to damage as the fact that anything fatal is quickly reversed. The Valkyries can still die in any way that a mortal would, but they would quickly regenerate and revive.
As you can probably guess, this will be a darker RP, with violence and non-con being a certainty. Any other kinks or story elements can be worked in, and the only limits are that of my partner.
A couple of final notes. First, they are called Valkyries, but the immortals do not need to be female. Blame the person who first found an immortal and decided to give her a flashy name. Secondly, this RP is imagined as being modern fantasy, but can be reworked into just about any setting.
If you think this might be an interesting plot, let me know and we can work out details.