Sam would never forget the day he didn't knock on Dean's door. The moment he stepped over the threshold he knew he'd overstepped a bound. He came face to ass with Dean -with Dean's lubed ass…- uncertain of what to do, he stood and watched his brother pushing back on Castiel's fingers.
Dean saw him first and moaned his name. "Sammy….Go!"
Cas smiled at Sam and shook his head. "No, you don't mean that Dean. Come here Sam."
Sam began walking towards them, it was as though Cas was in control of his every move. He stood beside the bed, and watched numbly as Cas used one hand to undress him. Cas leaned up and tugged Sam down for a kiss.
"Dean's been waiting for the right time to ask. I think this is the perfect setting." Castiel growled lowly.
Sam panted softly. "You want me to-?"
"Dean never would have said anything." Cas kissed him. "We both want you Sam, lay down beside Dean."
Cas gently removed his fingers from Dean's ass, and guided Sam down onto his back beside his brother. Cas gently rubbed Sam's cock to life. Sam moaned and turned his head, he was met with Dean's worried green eyes.
"Sammy you don't have to, I know this is twisted and wrong-"
"Dean...I want this." Sam said softly.
Dean shut his eyes tightly and took a deep breath, when he opened them Sam saw relief and joy. Sam inched closer to steal a kiss from his brother. Dean willingly pressed back, moving onto his knees and leaning over Sam to deepen the kiss. Cas sat behind Dean stroking his thigh encouragingly.
"That's it Dean, you've waited so long for this." He murmured, kissing the soft skin of Dean's lower back.
Dean got between Sam's thighs and hitched his hips up so their cocks made contact. He lowered himself back and let Cas impale him. Dean moaned and Sam dragged his fingernails over his brothers shoulders.
Cas pressed close and kissed the back of Dean's neck, then he rested his chin on Dean's shoulder and watched the brothers kiss. Sam bucked his hips up eagerly against Dean's, causing Cas to sink deeper into his lover. Cas groaned and reached a hand down to rub Sam's pecs firmly.
The next few minutes passed in a blur for the three men as they moved to pleasure each other. Sam was pressing up desperately into Dean as precum eased their way, they moved slickly against each other. Sam hadn't known that Dean could produce so much slick, but Cas was milking him for all he was worth.
Overwhelmed by the experience Sam finished faster than the other two, he was followed by Dean and then by Cas. Dean cried out and threw a hand back to grip Castiel's thigh, keeping the angel buried deep inside as spunk filled his passage. It was the hottest thing Sam had ever seen and his cock gave an interested twitch as he watched the two men orgasming and enjoying each other.
The three lay panting, stroking each other's sensitive skin and kissing tenderly.
"So…." Sam hesitated.
"Why did we let you in?" Cas asked. "Ask Dean."
Sam looked at his brother who gulped and kissed him softly. "Love you Sammy, always have, always will."
Sam felt his insides warm at his brothers words, words that he didn't hear often. He nuzzled noses with Dean and then with Cas.
They moved around to get comfortable and settled in for a long sleep.