Manga are usually restricted when it comes to such explicit content. The industry has norms and expectations to maintain a certain level of decency, so depicting vaginas is commonly prohibited.
This kind of porn typically showcases scenarios where the female characters are portrayed as strong, perhaps in terms of physical strength or personality, while engaged in sexual acts. However, accessing or promoting such content is unethical and may be against the law in many places.
The main distinction of porn with a story genre from regular porn is the presence of a coherent narrative. Regular porn often jumps straight to the sexual action, while the story genre tries to add some kind of story framework around it. But in the end, both are adult-oriented and feature explicit sexual content.