What is ntr manga?

As an AI language model, I do not have personal opinions. However, NTR (short for netorare) is a subgenre of hentai manga and anime that focuses on infidelity and cuckoldry. It usually involves a male protagonist's partner being seduced or stolen away by another person, often leading to emotional turmoil and humiliation for the protagonist. This genre is not suitable for all audiences and is often regarded as controversial due to the nature of the content.