So. Homestuck is a webcomic by Andrew Hussie that ran from 2009 to 2016, and is in some ways still ongoing. It was very interactive-fiction-inspired, for example with the page-advancing links in the format of parser commands, and text adventure-like descriptions of room objects. In addition, there are interactive segments in the comic. So it makes sense that there will be fanfiction of Homestuck written as IF (although this is a twine game, not a parser game, there are other parser homestuck fanfics). Among the relatively limited world of Homestuck fangames, this is one of my favorites.
This is a story taking place from the perspective of Jane Crocker, one of the main characters of Act 6 of Homestuck. She has just been mind-controlled by the Condesce, an insectoid fish alien who is the empress of the mostly extinct troll race and is also Betty Crocker, Jane's adoptive ancestor (it makes sense in context, sort of). Now, Jane serves the Condesce's will, doing her bidding in her plan to recreate the old troll empire. She's forced to hurt her friends and do stuff against her former interests.
The story is about Jane's existence under mind control. There are always multiple options on each screen, to try to get free or fight back, but clicking on any but the "correct" one, the options that commit harm and are forced by mind control, causes the screen to shake and flash red. Clicking on these links too much will cause Jane's brain to explode. "Denial of agency" and "player complicity" are pretty common techniques in IF, but I think this game works particularly well. Also I enjoyed the writing which captures the flavor of the darker side of the webcomic, while having its own distinct prose style.