[Allen had been working nearby, he hadn't seen Lucrezia come in at all since he had been so focused on his work, working so hard to ignore everything. ]
[It's not until he hears the sound of House stumbling does he look up. Look up to see his teacher with a knife in his chest, put there by some woman he's never seen before- doesn't recognize.]
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[It's not until he hears the sound of House stumbling does he look up. Look up to see his teacher with a knife in his chest, put there by some woman he's never seen before- doesn't recognize.]
[She stabbed his teacher. She killed House. ]