I'd say yes, he should be worried and check but in these kind of manhwas they're...different? Don't want it to seem like as if I'm defending Hunter but its usually because ( even in real life ) when something huge stretches your area, whether it's a vagina or an anus, you're bound to feel pain (given how thick hunter is) because no amount of stretching can make u ready for that size. Usually for women it's best to wait 1-2 minutes to let them adjust to the size but idk what it's like for men. So yujin probably felt something being torn when it reality he's just too tight and he's being stretched way too fast (not that good) while hunter doesn't check because..well I'm assuming he's looking down when he thrusts and can see / feel if there's blood or not coming from Yujin's area. (Idk why I'm acting as if that whole scene was on video but that's how I imagined it to give you a realistic(?) Explanation)
Totally get what you're saying.
I raised my question because I've had say gex before and it can take upto a whole day just to relax a man, especially someone who's never taken another man before so I'm not even gonna compare this to irl.
Also, I was referencing the time where Aaron used the dildo and then his own to fuck Yujin and what you're saying is correct but that would apply to a woman and not a man because the thing that felt like tearing to Yujin was the rectum, not the anus itself, which will likely not bleed out and would instead just bleed internally.
Don't know why I'm taking this so seriously but yeah, I was a bit concerned.
And though it CAN take 1 to 2 minutes to relax a lady, it's not advisable and you should take as much time as you can!

A top wouldn't actually know if they did tear the bottom though, right? It's crazy how Aaron hunter can confidently say nothing is torn when Yujin says he thinks Aaron "tore something". Shouldn't he be a little worried at least?