I can't believe you actually went with the forced cannibalism plot. Otherwise, this is alright. The anomaly is one of those simple attractive premises, though admittedly I found its particular gimmick rather dull.
The GEAR document is pretty much pointless, save for the ending. Having it produce a weird sentient being is… ok? Having the anomaly output something weird for drama is a very played-out development, if I'm being honest, and it's never built upon afterwards.
As for the last part… Timothy did it better, really. The anomaly is supposed to act as a twist on the premise, but it could've been taken out and the story would've been functionally identical.
It's a competent article, though. I don't have much to say about the parts that work. Whether I give this a 3/5 or a 4/5 depends on how generous I'm feeling, and I suppose I'll be generous today.
RPC-599 appears externally to be a 1.0m by 1.0m steel storage box with a circular opening on one side.
It exists in two dimensions?