I agree with you, 99.99% of manhwas without ntr are very boring with a repetitive concept
But the manhwas that are centered on ntr, half of them have very heavy ntr, these manhwas are known as heartbreakn, they contain very cruel words and events (emotions that I have not experienced in adult games) for example, the manhwa: So close, yet so far which plays with the reader's emotions or By Chance
But the other half of the manhwas that are based on ntr are great and I personally enjoyed them a lot, for example: E Romance, Run Away, Everything Is Agreed