Just my own two (very evil) cents - the Other Castiel loves making Sam giggle - just LOVES making that deep voice get high-pitched and talking (pleading) faster than a caffeinated chipmunk on helium. And getting Sam to say whatever truly nutter-butter crazy thing he can cook up (and that can be a LOT) - but it's never anything that would be bad for Sam's self-esteem. "I want you hear you say you enjoy this." "I want to hear you say you love being able to laugh."
Ohhhhh, thatās more cruel for Sam than an interrogation scene for information he doesnāt even know. Which theyāve tried, but sometimes trauma rears up in unexpected ways and brings things to a crashing halt. And AU!Cas isnāt great at aftercare, which really shouldnāt have been a surprise. It takes a couple of weeks for Sam to feel up to trying anything again. But they both take it slow, and Castiel gets more practice in being careful. (Heās still not tender, by any means, but he eventually finds a balance that works for them.)
It doesnāt take long after that for Castiel to realize thereās a new battle in the wake of that experience. Perhaps itās not actually new, but itās raw: Sam believes that their arrangement isnāt okay. That itās some wrong thing that feels good only because Sam is wrong. (āLike the demon blood,ā Sam admits quietly, once.) This Castiel may be sharp and jagged and welded together at odd angles, but heās still an angel with an existentially cracked chassis. The ātoo much heartā has been burned out of him more times than can be counted, but thereās a twisted, remnant tumor of it that beats unevenly in the dark recesses of his being. (In time, it will grow, like it always has, like it always will.)
So their arrangement begins collecting strange add-ons. The safeword becomes āfelicity,ā then āparagon,ā then āimpeccable.ā One of their games starts happening more often, the one where Sam will discover a folded scrap of paper somewhere in his daily path with an innocuous phrase scrawled on it, and later ā whether that day or the next week ā that phrase is wrung out of him in cascades of laughter. One paper Sam finds that makes him really raise his eyebrows upon reading it is: āLaughter is the best medicine.ā
He manages to handle that one. But two days later, itās āI deserve the things I want,ā and Sam⦠almost safewords instead. Yeah, heās surprised, too. He just⦠canāt make his mouth say it. Everything just gets too tangled up.
After that, the phrases go back to nonsense for a while: āHoney and milk are under my tongue,ā and āMy navel is like a round goblet, which wanteth not liquor,ā and āI am fair as the moon, clear as the sun, and terrible as an army with banners.ā They would make him laugh, but well, heās already laughing anyway when he wheezes them out.
(It takes a few more clues to figure it out, and a double-check with Google, but eventually Sam asks, āHey, why are you making me quote Song of Solomon?ā after he gets his breath back. Castiel just hands him a bottle of water and doesnāt reply.)
The next one is āI am worthy.ā
By now, Samās tongue is a little less uptight. Itās still a bit weird, but he says it ā once heās been tickled to the brink of reason, of course. Heās slightly astonished to discover his toes are still alive and attached to his body after that one.
Itās two weeks, then, until he finds a slip of paper in his underwear drawer that says āI donāt want this to stop yetā on one side, and āThank you, that was perfectā on the other.
Brows furrowed, he decides to go find Castiel and ask⦠something. He doesnāt know what his question even is, but heās not too sure about the implications here and he wants some time to process.
Heās abducted the moment he walks out of the room.
Thereās a blindfold this time, which hasnāt happened since the first interrogation-gone-bad. The usual game goes hard and fast, ramping Samās body up to the point of desperation and holding him there until he breaks. But this time, there are feathers tracing his legs and fingertips sweeping gently across his tummy, and sure, it tickles, but itās⦠kind of great? And he doesnāt have to face whatever awkwardness might be in that realization, because he canāt see, and somehow that makes him feel safely hidden even while his body is exposed.
Spilling the given phrase has always marked his defeat and the end of their sessions, but this time he works up the courage to giggle out, āI donāt want this to stop yetā while itās still true. And rather than ending, or slowing, or speeding up, or anything ā the soft barrage just keeps pace. In that moment, Sam hits euphoria.
He has no idea how long the second half goes on. The blindfold keeps him focused on nothing but the sensation, and itās good, itās so good. He giggles, and squirms, and laughs, and hums. Heās never been tickled like this, and he dazedly realizes that thereās something else, too, thatās not just gentle fingertips and delicate feathers. It must be Castielās grace, only because thereās no other explanation for the preciously soft tingling spreading through his entire body. Usually, an assault of grace is overwhelming, like sudden loud static with the volume turned all the way up. But these tingles are drowning him in pleasure. Sam writhes until his muscles give out, smiles until his cheeks go slack, laughs until his belly goes soft. Heās on another plane.
The tickly haze carries him until heās just⦠tired. Heaviness weighs on his bones and he keeps drifting to dreamlike places behind his eyelids. Itās a murmur of pure satiation when he breathes, āThank you, that was perfect.ā
A rustle of wings is the only thing he senses before he sleeps.
Grace tickle-vibrates Samās ribcage like a full hive of bees, and heās losing his mind.
Itās been a number of sessions since his visit to that alternate plane of existence. Heās been coerced into saying all sorts of things heād usually find embarrassing, but he hasnāt had as much difficulty with them lately, for whatever reason.
He would, he wants to, but it tickles, tickles, tickles, and he canāt, he canāt.
The vibration drops down a level in his ribs, and at least Sam can gasp for breath now, but the bee-buzzing suddenly reappears in his ears. Holy crap, he had no idea he could be so debilitatingly ticklish there ā itās like hundreds of fluttering moths wielding tiny electric toothbrushes have swarmed his ears, inside and out, and he squeals.
Sam canāt hear a goddamn thing past the buzzing tickle torture, but he can feel his throat crying out, āI love being tickled like this!ā between wild rips of laughter.
And fuck it all, but itās true. Maybe early on, this arrangement was more about punishing his body into submission, forcing on it something that left no choice but to be given in to, because choosing that was at least something he could control in a world so fiercely out of it. But somehow ā heās not entirely sure how ā
ā it now feels more like something he chooses because he wants it, and thatās allowed.
The buzzing moths finally let up, seemingly satisfied by his proclamation. Sam shudders, certain his head will be ringing for hours, the aftermath leaving him unable to walk a straight line as if he just came off the worldās craziest tilt-a-whirl.
A scant few of the moths flit down to his navel, just to keep him giggling while his body winds down.
The blindfold keeps Sam from seeing it, but Castiel smiles.