SPOILERS:
All of the corruption was meant to happen, it is the byproduct of Monika tampering with the game files to get you alone (as seen in act 3). The game is meant to show:
"An exception occured
File "game/script-ch5.rpy," line 307
See traceback.txt for details"
In the traceback.txt is the line: "Oh jeez...I didn't break anything, did I? Hold on a sec, I can probably fix this...I think...Actually, you know what? This would probably be a lot easier if I just deleted her. She's the one who's making this so difficult. Ahaha! Well, here's goes nothing."
This is Monika talking directly to the player.