"Is my blood really that sweet?"
"Of course. You are remarkably sweeter than the most powerful succubus in our territory."
"Succubus, huh." Uriel drew out her mouth and looked Elise in the eye. "So you'd tasted one."
"Yes. Though they are not as rich as dragons, they are abundantly available. If there's no supply of dragons, I just have the succubus matriarch visit my quarter."
"That matriarch must be powerful to be recognized by you."
"That's right. If my predictions were right, she would have evolved into a Nightmare within a few years."
Once a succubus reaches Level 600, she becomes a Nightmare, a race said to be on par with a True Vampire or even a Demon Lord.
The Succubus race is an all-female race, which obliges them to mate with other races. Being a single-gender race brought them to their depopulation.
