Banned because letting an alien soldier*, who can bend reality to his whims, who served under the elite guard of a militaristic empire with no equivalent of the Geneva Conventions, an empire that has no qualms about "coercing" information out of their prisoners through utterly horrific torture methods, and considers anyone who has no cybernetic or bionic modifications a lesser being, among other delightful details,*gasp* have his way with a shouty zealot is worse than giving him a swirly.
TL;DR: Banned cuz Alien > toilet
*He's actually quite friendly, if a bit aloof, once you get to know him.