"Dummied Out - When some feature, level, monster or something else was meant to be put in a game but ultimately ended up getting cut out for whatever reason. Except instead of deleting the data entirely, the programmers just remove all legitimate ways to access it, leaving pieces of it in the game code (textures, models, sprites, etc.). For instance, setting the game so a particular enemy never actually spawns, or removing all entrances to a level that was never finished." - TVTropes
"Human Sue" talksprites are associated with Beta Cave Story. I'm not sure how exactly, perhaps initially Sue was supposed to be a human.