One of the photo references:

(a month after Lanza's 18th birthday)

(The others were when Lanza was 16 and when Lanza was 20 playing Dance Dance Revolution)

The text saying "no, don't worry, I'm not going to molest you now that we're alone just because I sound like a pedophile" came from one of his Youtube videos under the handle "CulturalPhilistine"