Magnetic (3.5e Flaw)
From D&D Wiki
You are very attractive, but not in the way you might have hoped.
Prerequisite: You must be wholly or partially made of a ferromagnetic material such as iron or steel.
Effect: You suffer a -1 penalty to your AC against attacks made with metallic weapons. Furthermore, all melee and ranged attacks made with metallic weapons (or metal heads, such as arrows and spears) act as if they are seeking weapons when targeting you. Finally, your armor check penalty increases by 2 when wearing metal armor.