Board Thread:Legitimate Canon Questions/@comment-108.249.140.237-20150404103145/@comment-11533671-20150405040415

Possessing Scott was out of the question, or so I assume, since "You can't be a fox and a wolf". ([]) Controlling one, as it did with Isaac, seems to work however.

Allison seemed like a pretty tough gal and could be headstrong. I would assume that having Gerard, her mother, father and Kate helped develop her mental resolve. She was able to pass the scrutiny of all of them at one time or another at least.

Stiles has shown little to no resolve at keeping his thoughts/emotions in check very well and is prone to impulsiveness. The most significant part though is that Stiles never got over his mother's death and blames himself. All of that could leave a mental opening for the Nogitsune to exploit.

In short, Stiles probably had a larger doorway than the others. At least, that is my personal assessment.