You probably have red the description, so you already know what the girl MC is trying to achieve - protecting her chastity from the non-existent thread of a classmate of hers fucking her, which he wouldn't ever do (not in the rapey way, she seems to think must be the norm, at least). I am not going into how she basically assumes that he will rape her and has no issue with that, but only with the losing-her-verginity part of it, which you might find strange (I do), but whatever. Back to the topic: So, we know the manga is about a girl misunderstanding what the boy MC is trying to tell her. Mild spoiler ahead ...
Each act (you know, "act" ... if you will) is introduced by her wildly misunderstanding something the boy MC says and interpreting whatever as a declaration of war (= intention of sexual assault). Then she immediately reacts following the idea of Offence Is the Best Defence in that she will
- somehow blindfold the boy MC,
- whip his dick out and
- get him off by simulating penetration with whatever she has on hand.
Now, that alone sounds kind of funny. And in the beginning it is ... sometimes. If you overlook the ridiculousness of her "techniques" which, I assume, are supposed to be part of the fun (the fun for you, the reader, you know, as in: the gags ... to be fair, they really are funny in some instances), the big problem lies in the introdutcions.
... aaand spoiler out: These misunderstandings heavily rely on Japanese word play that doesn't translate well to English; in fact, after a few chapters in, most of the time, it doesn't translate at all -- meaning, unless you know and understand the Japanese original (or can recreate it from the translation), most of her misunderstandings make no sense whatsoever. It just doesn't work in English, not at all. It is literally one person saying something and the other person understanding something completely different and no connection inbetween ... and you, the reader, being all WTF?! As the avid consumer of fiction that you are, you are very familiar with the concept of Suspension of Disbelief. And while that concept can be applied here, too, in that you may not always need to comprehend (and/or agree with) everything the story gives you in order to get the gist of it and maybe get a laugh out of a gag, it only takes you so far ... definitely not far enough here. So, the manga may be genuinely funny in its own language - I can't tell -, but if so, it is definitely killed by translation. To make that clear, I'm not blaming the translators or saying they do a bad job. Fuck, not at all! I think, it just doesn't work in English, unless you carefully re-engineer the original wordplay in English ... which may be completely imposible most of the time for all I (don't) know.