But let's start from the beginning.
The story revolves around the meeting of two people, a man (the player) and a woman (Caroline), and how - in a few days - things can go off-scale with no apparent motive. A horror setting I wouldn't call it: maybe, just maybe, more of a Von Trier or Lynch atmosphere, imbued with layers of other sentiments which come - undoubtedly - from the player himself, namely: me.
To avoid spoilers, let's just say that a very regular date turns into something sooooo much far-fletched that the game itself could have been broken to me in a few minutes if not for something that came from the narration itself. And from what I unconsciously put in it.
The antagonist, in the given case Caroline herself, is a distant woman - from what we can see since the very beginning, disturbed in many ways - who starts a game of tag which eventually will end up in disaster. She's patronizing, but more than that, bully. The kind of bully that pushes you around without you even noticing. Creepy, in many ways. Way creepier than the intended-to-be-creepy actors in this dark comedy. All you do (or the story lets you do) is following her into a dreamlike sequence after the other until the final conclusions. Which are at least three, all of them feeling decapitated in some way (the story ends with the text fading to white, leaving you nothing to do but close the browser)*.
There are two main ways to follow the script. One, the least interesting - and, I would say, the least probable to be intended by the author - is to act like a male teen on the internet. You just do whatever it's needed to come to the final part of the story, where sex is involved. Although I don't want to believe that this game is played as a piece of AIF*, there is the chance of it happening. In case, you will be disappointed. The (again) dreamlike sex sequence is so convoluted that you may very well buy a porn comic-book from the Thirties and enjoy yourself.
The second one - the one that I experienced - is disturbing. And - fortunately - thought provoking. It depends on how you unconsciously decide to be part of the story.
To me, it was like being in The Stranger by Albert Camus, playing the role of a man with no agency in the world and no will to have any. I was part of the problem, and part of the story, as well as Caroline. I was dragged in - and dragged around - by a being with some ascendent on me (I never thought it was sex: the game soon makes clear of itself about what kind of story to expect. The very title aims at something creepy, not sexy), never trying to escape my fate, just distantly recording facts that, in most cases, were unimportant facts. Some have pointed to one single event (the discovering of the Bible in Caroline's bookshelf) as useless in terms of describing the character. Well, I sensed that nothing in Caroline was so important. I was in a boat with no oar, painlessly floating towards something that I couldn't - but must importantly, wouldn't - avoid.
This is the reason why I want to believe that the non-perfect input mechanism of the story is not coincidental.
Having to type letter by letter every choice into the prompt adds an unprecedented bond with the game: you can't simply mash at buttons to skip parts or to get to the end; you have to painstakingly follow the route, being very certain as to what to do next. While this would obviously be a mistake in many other kind of stories, in the given case it's a perfect way to have you feel the agony of (or the lack of interest in) following Caroline in all her nonsense. Again, Camus comes to the mind: how may times, during the reading of the book, you wanted to scream "do something, you idiot!"? How many times you were uneasy at the lack of personality of the protagonist?
More so: typing adds to the sense of tension of being with an oppressive partner. The sense of slavery of being dragged around. You just have the same two choices of the majority of WB games out there, still you have to bloody type in letter by letter, avoiding any mistake in the process. Christ dragging his cross to the Golgotha.
And, like the Christ, I felt like I actually wanted to drag that cross. Something that not many games have achieved with me before.
I don't know what this sums up to (and YMMV), but I felt this game. I felt it crawling under my skin, so much that I had no problem going in three times to understand what it was about.
Caroline is not a short story, if compared to the medium's average, though it is short enough to avoid being a burden. And I want to believe this was done by design and not by mere luck - as sometimes may happen. The prose is cut to the bone with alternating outcomes: while sometimes it sounds necessary, in others I would have preferred some tricks off the hat of the writer.
That said, as opposite to somebody's else opinion (can't remember who, sorry) I don't think having that much more detail about what's happening around or to the background of the characters would have made this story better. What we have to know - and feel - is essentially in there, between the dry sentences the protagonists share and the constant sense of despair inherently build into the flow of things.
* The abrupt endings. I don't think this is bad design. The story in this piece of IF is designed so it doesn't need a replay. The author is pretty much giving us a set of books and we decide (mid-game) which to read. This said, closing the story with no commentary, a proper ending sequence, or anything, has worked for me in making this game disturbing (in a good sense, I mean).
All in all, the game will be memorable up to the point when it spawns a dozen offsprings. The news of having to type text, as said above, won't work in the general case, and I wouldn't vote it for "best use of technology" at the Xyzzies.
Some will find Caroline a disturbing piece, some will ding it dull. Some will think it's a moral piece, others that it's just a lil, pointless piece of shit. In cases like this one, it's really hard to accomplish a good-for-all report.
And maybe, just maybe, this adds to the value.