True Succubus Kiss (3.5e Feat)
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 True Succubus Kiss [Abyssal Heritor]
The Succubus heritage in your blood turns your kiss into a life-sucking weapon.
Benefit: Once per day per Abyssal Heritor feat, you can change your poison kiss into the life-sucking kiss of a true Succubus. Instead of doing Strength damage, this kiss drains energy (Su) to bestow one negative level (DC 10 + half level + Cha to remove it), and you can plant a Suggestion (Su) to accept another kiss (Will save DC 10 + half level + Cha to resist). Using the kiss is a standard action. The target of the kiss must be willing, or the user must succeed at a touch attack during a grapple. This is a supernatural ability.
Special: This ability is hard to control, and you run into the danger of accidently draining someone you kiss. You must succeed at a Will save DC 25 to suppress this ability. You gain some control as you become stronger, and the DC is lowered by one for each Abyssal Heritor feat that you have.