A vigil? no. A devil? yes. He rejected normativity for his fetish, he enacted his sick justice against the grain of his society. He can't expect to just be allowed to easily cross to the other side.
Takigawa is either really trying to investigate who is the real Toilet Jacker or actually only decent person in the whole school, I don't think she is on Kitahara "kill list"... although have strange feeling she will be the next one...