User blog comment:Thailog/Ep. 205 "Beneath" discussion/@comment-47881-20120526211552/@comment-47881-20120526224801

Playable or not, Psimon is a character of the game, and as you pointed out, it takes place between season 1 and 2, thus after "Image" and before "Beneath", when he was supposed to be in a coma.