Dean's True Love

Sam stayed cuddled in his big brother's arms not noticing the click of the bathroom door or the entrace of his niece again. She tucked her bright hair behind her ears and smirked before she spoke "So, do you guys need like what? Ten minutes would that be sufficient? I could go out in the hall but if you're gonna be loud I will go to the car." Dean let go of Sam and glared, a bit amused at the girl.
"I'm hugging my little brother, that ok with you kid?" Mara shrugged and settled in an overstuffed, ugly Barney colored armchair.
"Whatever gets you through the night, Dean. And like by the way Uncle Sammy, do you ever clean that bathroom? It is fucking nasty." Before Sam could say anything, Dean shot up like a bullet and walked over to the girl, a very unhappy expression on his face. Sam really hoped he wouldn't lose it.
"Mara, I really don't want to get mad at you here but that was rude. I am you dad, don't call me Dean. If Sam's bathroom is nasty that's his business and I really do not want to hear you swearing, understand." Mara looked up at Dean, anger coloring her cheeks.
"You know what, you've officially been my father for 24 hours I'm not comfortable with calling you dad ok!? Uncle Sam's bathroom is gross and he should know it, and you swear why can't I?" Dean nearly growled and walked away from her for a moment.
Sam sighed and looked over at his niece and was about to speak, the fact that she kept saying uncle was not lost on him. But he noticed something, Mara's eyes tracked Dean's movements carefully, like she was studying him and needed to make sure she knew where he was at all times. Sam had seen his big brother do that with their father a million times, he had asked Dean once when they were teenagers why he did it. He told him it was because he only had one parent and he would not lose him, so he needed to be aware of him constantly. Mara had lost her mother and her grandparents, she might act like she hated Dean but there was no way in hell she would lose him too.
Dean started to walk over to Mara to start round two when the girl jumped up, pale as a ghost."We have to go." Sam and Dean both looked confused and then looked at her.
"Why Mara?" Sam asked softly. She swung in his direction, her eyes so identical to Dean's practically glowing and her hair moving slightly on a non existant breeze.
"He nearly killed you too can't you feel it? He's coming we have to go...NOW!" Mara ran to Dean and grabbed his hand pulling him with her, glancing desperately back at Sam. Dean looked at his little brother but followed his daughter anyway, watching as Sam grabbed his backpack. Even though he'd been at school for so long, Sam still kept a bag packed, habit from all those years of moving around.
Sam ran out after them suddenly worried as out of the corner of his eye he could see a dark figure standing in the middle of the living room, where they had all just been. When he got to the car Dean was holding Mara close to him and she was shaking, looking up at Sam with such sad eyes. No child should hurt like that. Dean glanced back at the apartment windows, in time to see the figure at the window minutes before it erupted in flames. Mara gasped and buried her face further into Dean's chest. The older Winchesters just stood and watched, wondering if it had been a warning or if the Demon really had been trying to hurt them.