The Vitality Demon was not one of the Demon King's soldiers, nor did it bow to any cult or banner. It was a free demon, born from the distorted lineage of succubus demons, yet warped into something far more peculiar. Where others of its kind fed on desire indiscriminately, it possessed a twisted preference that set it apart.
It hated women.
No— hate was not quite the right word. Women interfered. They disrupted its hunt, ruined the rhythm of its games, and more often than not, stole away what it wanted most.
He likes men, so he hates women who takes his men.
Women are meh. Men, on the other hand, were perfect. Fragile in ways they did not realize, overflowing with vitality, pride, ambition, and recklessness. When the demon took them into its embrace —when it "loved" them through flesh and breath— it could devour their vitality entirely, leaving behind nothing but an empty shell.
That was its gift. It was his one of the top three skill.
