This is my first story in this fandom.

Warning: Slight sexual situations. Mommy!kink.

Mothers don't do this; Stiles should know better than to play favorites at this point in time. He should know better because he's had a mother, unlike Isaac, to hug and cherish and learn from. There are certain things that no mother should ever do when it involves her own flesh and blood, when it involves her own son. Stiles knows this. Long before this had even started, he's held his morals close to his heart and never turned his back on them. He knows that no mother should have sex with her son, no mother should know how her son's cock feels inside her, no mother should let her son think that it's right. Yet he finds himself constantly feeding into this twisted, dark role that Isaac's created in his mind of how a real mother should be.

"Mommy, haven't I been a good boy?" Isaac questions, using that same enthusiastic, childish tone that breaks Stiles' resolve every single time; he knows exactly how to make Stiles want. He also knows how to give.

The words sound innocent enough to make anyone believe there are no ulterior motives, but Stiles knows better. Day after day, he falls into the same bed, beside the same person, due to the complex simplicity of the same words. Isaac is the child who cries and cries until he gets what he wants because you feel guilty. Lost and broken when he's alone and spoiled rotten to the core once he receives attention. In other words: What Isaac wants, Isaac gets. And he's greedy, fascinated by rebellion, so he takes, takes, takes what's given all for himself until there's no longer any point to share. Stiles is unselfish so he lets people have what they want, even if that means they use him for their own dark desires.

He spreads his legs willingly and says nothing when careful fingers begin to rub between his legs where no son should touch. They ask for permission yet never pause long enough for him to give an answer. He says nothing when those fingers push inside his body with a tenderness that should not be shared between mother and son. His relationship with his mother was nothing like this, never as impure and sinful. This is what Isaac always wants when he does something 'good' because this is what mommies do. Mommies take care of their sons and give them 'special treats' when they're good boys. Mommies give in to their sons needs and don't ask questions or disobey. To Isaac, Stiles is a mother so he shuts his mouth and does as he is told.

Never does he tell him that if this were real, it would not be tolerated; he shouldn't need anyone to tell him that.

Somewhere along the way, Isaac's father had broken him in ways no one has thought or seen as possible. Somehow he had damaged his morality, broke it and caused his son to build a model of how a real family should be on their terrible relationship. Something a wolf's bite cannot fix in the mind of a hopeless child who seeks things that are impossible and perverted in reality. The past abuse keeps him from speaking any variation of the word 'father', that's why there's always Mommy. He's from a dysfunctional family and thinks that it's normal how they, he and Stiles, work. Fathers abuse, hit, threaten and hurt you. Mothers clean up after fathers and fix you in any way possible because they did nothing to help you at all.

It never dawns on him that Mommy will have years of cleaning and fixing after everything Isaac's been through.

He shouldn't be here moaning, groaning, encouraging Isaac as he thrusts into his Mommy's body. He shouldn't be here whimpering, keening, begging for more of this immoral pleasure as he plays the role of Mommy for his lovely son. At this point, he is just as wicked as the other because he says things that can't be taken back. His words are filthy and disgusting in his throes of passion, ministering to something that far surpasses a small kink. But he knows that Isaac likes it, Isaac wants it, Isaac needs his words to make it real in his mind and he asks for nothing else from anyone. These are, this is, it's the only reason he needs to keep coming back whenever he is needed.

As always, their movements are gentle, slow and practiced. Now their kisses are sloppy, demanding and open-mouthed, their tongues meeting and muffling any noisy moans. Hands and fingers intertwine with his own as they're pushed down into the bed, the thrusts inside him becoming more frantic. The soft cries and pants that come from above only serve to heighten his desire to reach bliss and prompt his hips into meeting every push into his body.

"You're so good to me, Isaac," Stiles whispers into his ear, his legs and arms pulling him in deeper as he gets closer to the edge. "Now cum deep inside of Mommy like a good boy."

When they're laying side by side, spent and done for the night, Stiles plays a different role of Mommy, a different that's normal and a version he knows well. It is times like these that make him forget about all of the bad things and focus on the great things they have their relationship. These are the times when he's needed as a parent in ways that are seen in any other child. As Isaac falls asleep, he runs his fingers through his curly hair and kisses his forehead. If he wakes up in the middle of night sweating and panicky about nightmares, Stiles holds him close and tells him stories about the years when he had a mother until his breath evens out and he's certain that Isaac is sleep once again.

All of this is to help Isaac, he constantly has to remind himself, because what Daddy breaks, Mommy fixes and this is the only thing that Stiles can offer.