Side Effects

Regret

Stiles looked at Sam and tried to think of the best way to respond. He remembered what happened, or more like his little understanding of what happened. His body and mind were taken away from him again.
"I don't know... one minute I'm washing my face and the next... I'm not in control anymore." Stiles wasn't sure what they could make from his explanation, it was the truth at least. Any other explanation would paint him as a suspicious character, the truth, if Stiles has been right this whole time, will have these hunters see him as the victim.
Sam and Dean have heard this same explanation a thousand times, although, it was hard to believe a demon possession took place and the first objective was not to kill the Winchesters, but to escape them. Stiles took a look at the matching pensive and confused faces and decided to keep playing the clueless role for now.
"Please! you guys have to believe me!" Stiles pleaded as he stepped towards them, feigning desperation, he knew they'd believe him, they were hunters after all. Sam looked at Dean, it wasn't difficult to believe him, that was no longer the issue at hand, it was what they were going to do next that was the problem.
Sam turned back to Stiles,
"Stiles, it's okay, we believe you, just calm down." Stiles took audible deep breaths and moved to sit back down in the car seat, body still facing the Winchesters.
"Sam... what happened to me? I could barely stop myself from going back, I don't want to go back to those people." Stiles almost whispered, his tone dripping with fear and confusion. It wasn't particularly hard to dig up and imitate what he had felt after several encounters back home, back when it was all still new and terrifying. He needed to know what Sam knew about this, how to stop people from taking away his free will and forcing him to do unimaginable things. Stiles recalled his last few thoughts before the pain of resisting took over, this had to be the witch's doing, so far there were no other mystical creatures that could have a vendetta on Stiles.
         "You're okay now Stiles, whatever it was, you fought it and you won." Sam reassured, he approached Stiles slowly, and once he was close enough, he placed a hand on Stiles' shoulder. As he said these words as means of consoling Stiles and the emotional toll he should be experiencing, Sam couldn't help but ponder over his own words for a second. Stiles fought off something, something powerful enough to take over his body and mind, that was not only impressive, but skeptical.
        "I'll explain everything to you, I promise, let's just get out of here for now." Sam helped Stiles up and guided him in the direction of the Impala while he following slowly behind on purpose, taking a moment to let Dean fall in line with him.
        "Do you really think he can handle the truth about what we do?" Dean asked Sam, there were many ways it could go wrong, Dean just hoped Sam's judge of character wasn't skewed.
"Maybe it'll take some convincing, but yeah, after what happened, he probably wants answers more than anything, that's what we'll be giving him." Sam reasoned, he didn't know Stiles very well but however Stiles takes the information, Sam was sure he could handle it, at least for the small amount of time he'll need to confront it.
"More than we can say for everyone else we've saved, half of them probably needed a couple therapy sessions to convince themselves they imagined it." It was true, while a lot of people accepted their made up explanation, others wouldn't and sometimes can't handle it, especially when nobody would ever believe them.
         They reached the Impala, in which Stiles had already let himself in. Stiles didn't mind that the brothers were talking about him, he didn't blame them really, he's done the same. Right now, Stiles decided that his priority was dealing with this witch, she made the wrong choice in choosing to take over his being like she did, it was the final straw. When Sam said he'd explain everything, he had a feeling he really meant it, Scott and Stiles have said that phrase enough time to know when it's true, no more bogus explanations. After his planned performance of "discovering the truth about the supernatural", there wouldn't be any time to waste, he'd need to get to a computer at the very least. Resources were scarce for Stiles, he didn't have his usual set up, his own computer, the books he's collected, but then again, this wasn't his usual situation.
         The closest he's gotten to a witch was a druid and he didn't exactly have a ton of time for researching similar beings after she was gone. Certainly, Sam and Dean knew all about the witch's kind, if they've been doing this as long as he thinks, there was no way they don't, but that doesn't mean they can stop her before she tries to attack again. All the three of them had was a who, what, and a where, the where might not even be definite by now, Stiles needed a how and why. How because to prevent anything else from possessing him, Stiles had to know how she did it in the first place. Why because what was so special about him? The witch probably had an equal opportunity of mind controlling Sam, but she didn't, she also went out of her way to grab him, Stiles would prefer to think it was because of his ties to a true alpha and his pack but his instinct told him he wasn't so lucky. That's another 'why', why did she take Sam too? Factoring in Sam's capture and getting access to right information was how Stiles planned on cracking open this nightmare mystery.
They drove off, once again, as far away as they could get from the witch, her spell was a set back, but it also backfired. She would only live long enough to regret it.