And that was that then, to Al's logic-driven mind.
In the end, it didn't matter that Lily felt pride or horror, or love, or fear. It didn't matter how much contradictions were in her mind or heart, there was a cold brutal fact of intent beyond all the confusion of feelings that still existed in her.
She knew. She helped kill Dad.
As Al heard that, it wasn't horror that drove Al's thoughts. It wasn't horror, or revenge, or morbidity - just pure shock and incredible loss and all those thousands of moments of unvoiced and shoved-down grief since the day he learned about his parents' death.
His eyelids were squeezed shut until he only saw bright-red and that red dimmed to dark, not nearly fast enough. His forehead was pressed so hard against the cross of Severus' arms, and his throat seized up until he choked.
Something warm and itchy hit his eyes and dull ache filled his head, and for the first time since he remembered himself exist, and think, and reason, Al cried.