"I didn't mean to." Dean fell limply against Sam's chest, head tilted upward, and pressed a desperate, open-mouthed kiss to his neck.
Sam pushed him back but didn't let go, just held him at arms-length, one hand on either side of his face. "Whoa, whoa, hey. It's me. It's Sam. What're you doing?"
"Please, Sammy," Dean begged, eyes wide and wrecked, reaching out to cling to Sam's shirt with his fists, leaving half-moon bloodstains in the gray fabric with every fingernail that made contact. "Please, I can't hate anymore. I hate Cain for puttin' this goddamn mark on me in the first place, I hate Cas for not killin' me when he had the chance, I hate Claire for comin' back here after Cas tried to keep her safe, and I fuckin' hate myself for doin' this. I hate myself so much, and I just... I need to feel somethin' else. Please."
"Okay," Sam murmured, pulling Dean closer again. He hesitated for a heartbeat and then leaned in to gently, barely brush their lips together. It definitely didn't fall under the category of brotherly love, but it wasn't much, and he was desperate. He needed something to ground Dean. To stabilize him. "Okay. It's okay. I'll just have to love you enough for both of us."