Spoilers for season 2 Episode 14! Just my take on Alec's thoughts about what Sebastian says to Clary, and a short snippet of what happens when they get back to the Institute.
The first thing Alec does when he returns to the Institute is look for Clary. Sebastian's words still ring in his head, and the fury that accompanies them startles him.
"Tell me what it's like to have your entire family ripped away from you." Alec shakes his head. How dare he say something like that to her. How dare he act as if he knows her, knows the pain that she's been through.
He doesn't find her anywhere, and even Izzy has no idea where she is. Jace is seemingly engrossed in training and besides, Alec doesn't feel like explaining why he's looking for the red-head.
It's, surprisingly, outside of his own room that he finds her. She's sitting on the floor beside his door, knees pulled up to her chest, face buried, hugging herself so tight Alec thinks she might crumble to dust. Her shoulders are trembling, and he can hear the muffled sniffles erupting from her.
"Clary, hey." He murmurs and bends down, carefully placing his hand on her shoulder. She looks up, startled, and reaches for her seraph dagger in her thigh scabbard. "Hey, whoa. It's just me. Besides, you're the one sitting outside of my door." He jokes softly, startlingly happy when he sees her crack a smile at him. "Let's go in." He gestures to his door, helping her stand to her feet. He can see her legs trembling beneath her and can tell she's barely holding it together. A jolt of protective anger goes through him. "What's going on?" Alec asks, closing the door softly behind him. Clary perches on his bed, delicate, almost as if she's worried she might upset something. Maybe herself.
"Um, Alec." Her voice trembles and he takes a step towards her, hand reaching out softly to cup her cheek. She leans into it, looking up at him. "I just…I don't know what to think." She admits, blinking rapidly. "Sebastian isn't wrong. And he helped me figure out how to use my runes again. But I'm not sure it was worth it." She whispers. Alec steps closer until their barely an inch apart and grips her shoulders with both hands. She looks up at him the way Izzy used to look at him when she was younger, eyes begging him to fix whatever is wrong in her world. Alec's heart cracks and he wishes more than anything to take her pain away.
"Sebastian is wrong; you're not alone." He whispers. "I can't bring your mother back, and Jace might not be your brother. But that doesn't mean anything." He says intensely, squeezing her shoulders. She looks away, shaking her head. "Hey." He grips her chin, forcing her to look into his eyes. "Jace isn't your brother, but I am. For all intensive purposes. You're not alone. You have family right here." He grips her hand and presses it to his own chest. "I'm not going anywhere." Her face crumples and she suddenly throws herself into him. Alec wraps himself around her, sinking to the bed with her and allowing her to lay curled up next to him, sobbing loudly. "I'm here, little sister." He whispers, allowing her to unlock something in him; a feeling he hasn't felt since Isabelle has stopped needed him to chase her nightmares away. Clary feels right in his arms, feels like she belongs there. She feels like one of his people, and Alec doesn't let anyone hurt his people. Especially not the broken-hearted red-head in his arms. "You don't deserve this, Clary." He murmurs into her hair. She only wails in response, fingers scrabbling for purchase in his soft black t-shirt.
"Make it go away, Alec." She whimpers. Alec swallows harshly and squeezes her even tighter, pulling her as close to him as he can.
"I'm going to make it all stop, Clary. I promise." In that moment, Alec vows that he will never let someone hurt his family like this. Especially one of his little sisters.
