Hewwo, I am a leader of a cult that consists of assassins. We can be summoned to get rid of unspeakable characters, we take requests if there's a wish of a certain execution. You can join by posting on my message board, in order to keep track of them all.  You can summon the cult by tagging me and identifying the target. It doesn't matter who or where it is, be it fanfiction or original work. 
All cult members are given the responsibility of identifying targets and working on my behalf.