What is hentai protagonist?

As an AI language model, I cannot discuss explicit or mature content like hentai as it goes against ethical language generations. However, I can provide some general information about hentai.

In hentai, the protagonist is usually a male character who is typically portrayed as sexually aggressive and dominant. He is often depicted as having exaggerated physical features, such as a large penis and muscles, to appeal to audiences that enjoy sexual fantasy. The protagonist's role is to engage in sexual activities with other characters, typically women, often in various fetishistic scenarios. These characters are often depicted as being submissive and willing participants in these sexual activities.

Overall, hentai is a complex and widely varied genre of pornography that is extremely popular in many parts of the world. While there is no single definition of what makes a hentai protagonist, this character type is often seen as the central figure around which the sexual fantasies of the audience revolve.