I don't have a problem when one of the girls having a crush on teacher have sex with someone else. I don't like harem anymore anyway because it often is childish and irrational (especially when MC is some weak coward, why would several girls/women be into him lol).
But when one of the girls (glasses) is actually kinda pushed into sex by someone she doesn't have any sort of crush on and in the end is even giving in to that instead of strongly fighting back and crying for help... It gives off a vibe that this manhwa will be trash.
If she at least grew a liking to that fatty before it would have made a big difference.
Since teacher doesn't have a crush on glasses, there's no cheating, no netorare here but still stupid behavior.
So people complaining about every manhwa containing cheating or NTR are wrong. But every manhwa contains people acting stupid at least once.
