Normalization is a process by which the populace besides deadened to a subject. Or, that's the usage of the word I'm using, so if you're using something else, you gotta let me know.

This particular comic does the opposite of that. Some comics might contribute to normalization, but this one makes the matter more confrontational and less able to be pushed aside.

This is done by starting off with the usual "joke" of the young person enjoying the sexual activity, thus it must be okay that it happened. But, and this is the key to the to whole way this comic in specific and c&h in general work, the child is obviously, visibly injured.

The father, expresses shock at the broken arm, which can be taken as the father minimising the non physical harm, or that the physical takes precedence. Since physical injury should be addressed first, I don't see a problem with the latter at all. The first seems unlikely based on the history of the comic, but I wouldn't argue about it.

Then, and again, this is the key to it all, the injury is from inappropriate praise for being abused sexually. The child figure having a broken arm acknowledges that the child had some degree of outwardly positive reaction, i.e. high fiving, but was blind to the harm involved by way of taking that celebration so far that an external harm occurred.

If a real child were to celebrate having sexual interaction with their teacher, they would be inadvertently causing extra harm to themselves, and the reinforcement of the idea of being "lucky" to have a teacher make out with a student would deepen that harm.

So, the broken arm becomes symbolic of how destructive that idea is. The idea that because a child has a penis, or is otherwise viewed as male, they must enjoy sexual attention of any adult (though the social norm is for that to be assumed with a female abuser) because they got laid, is now subverted and shown to be as broken as the arm in the comic.

Now, you don't have to agree with that interpretation. But, cyanide and happiness has a long history of subverting broken social norms in this exact way. They use dark, ugly humor to both shine a light on the horrors of humanity, but give us a way to release that ugliness and the trauma of it through laughter. So I would argue that it is very unlikely that would have made this comic as yet another form of diminishing the effects of abuse, or normalization of abuse. It just doesn't match their overall ethos.

Plus, look at the final panel, at the dad. Look at his face. You kinda have to be familiar with the c&h style to pick up on it, but that facial expression isn't making light of anything. When they use smiles and glee via facial expression, it's hyper exaggerated. Usually when smiling or laughing would be inappropriate were it the real world.

But here, they've chosen to not use exaggerated happiness in that final panel. That suggests that they treated this subject matter differently than they might normally. A final panel in their normal over the top way would be the dad high fiving the other arm. The panel as out is drawn is unusual in that regard, it stands out. To me, and I've enjoyed their comics for a good decade or so iirc, this specific comic is exceptionally well crafted to not make light of the subject matter, or make a bad attempt at making fun of the usual "lucky kid" jokes and failing.

But listen. The use of humor around unpleasant subject matters is always a tricky thing. It is absolutely okay to make jokes about the horrors of life, and there's really no limits to what subjects are and aren't addressable with humor. But it's difficult because it's easy to fuck it up. It's also difficult because even when you don't fuck it up, some folks aren't in a place where they can joke about it.

I don't think they fucked this one up. I'd say they perfectly nailed walking up to the line on this subject, putting their toes against it, and said, "nope, that's far enough."

Like I said, you might not agree that they succeed in walking that line. That's perfectly acceptable. And it's perfectly acceptable that you have an issue with that subject being addressed with humor.

No buts. You aren't doing anything wrong.

I would, however, request that you remember that you asked for an explanation of how making comics like this aren't inherently normalization. I stayed with this comic as the example because look at the wall of text it takes to parse just this comic. Trying to give you an explanation for all comics/jokes would take days to work up, and be way longer than the character limit. So, if you disagree, keep all that in mind if/when you respond. If you didn't want an actual explanation, and were just wanting to vent on the subject, it wasn't evident enough in your comment. I'm giving you what you asked for, the the best of my ability.