Theo drew in a sharp breath when Snape mentioned his father, as though he was shocked to hear someone else speak of him. He rubbed at his arm then slipped his hand to his hair, tugging at it and whimpering, distressed.
"Gone, gone and back again, back again, always-" he shuddered. "Keeps coming back and back and back and, and what can stop him, nothing can stop him, nothing, no locked doors, no h-hiding under the bed, no, nothing, nothing, only locked, locked up in Greg's mind, but no, even there-" he bit off with a sob and curled over into himself.