Rank 1 Increases the effect of your Succubus' and Incubus' Lash of Pain and Soothing Kiss spells by 10%, and increases the duration of your Succubus' and Incubus' Seduction and Lesser Invisibility spells by 10%.
Rank 2 Increases the effect of your Succubus' and Incubus' Lash of Pain and Soothing Kiss spells by 20%, and increases the duration of your Succubus' and Incubus' Seduction and Lesser Invisibility spells by 20%.
Rank 3 Increases the effect of your Succubus' and Incubus' Lash of Pain and Soothing Kiss spells by 30%, and increases the duration of your Succubus' and Incubus' Seduction and Lesser Invisibility spells by 30%.