A link between eras.

I can, in principle, write a story even on my own. But I would like everyone who is interested in it to participate. But I will continue.
... Krigans, Devils, Demons, Infernal... They have many names. What they call themselves is a mystery to everyone. To find out, you have to become one of them. That's how Succubi appeared - former people who became too close to Darkness. They received their answer as a reward, and something else - the ability to drain life force from their sexual partners.