Corruptible (3.5e Flaw)
From D&D Wiki
The character is easily led astray, even to the potentially fatal detriment of other party members.
Prerequisite: Any non-good alignment
Effect: You take a -4 penalty to will saves against mind-affecting and compulsion effects. Furthermore, you are not granted additional saves when confronted with a suggestion that might conflict with your ethics or morals, nor do spells automatically fail when if you are compelled to harm something or someone, such as with the suggestion spell.