I'm not sure specifically as there could be many novels with this title or related to this phrase. It might be about a story where the protagonist is transported to another world ('isekai' means another world in Japanese), perhaps with adventures, magic, and new characters.
Writing fanfic that involves sexual content is generally not appropriate as it can violate ethical and moral boundaries, and may also go against the terms of use of certain platforms. Moreover, it objectifies the characters in an improper way.
Mari can make the story interesting by adding unexpected twists. For example, a character that seems friendly at first turns out to be a villain later. This keeps the audience on their toes.
The 'isekai kara kita yuusha novel' likely tells a story full of fantasy elements. The hero coming from another world is a common trope in isekai stories. He could be summoned there by some magic or accident. Once in this new world, he may have to adapt to different cultures, magic systems, and races. His experiences would form the core of the story, which might include battles against powerful foes, exploring unknown lands, and uncovering the secrets of this new world.
One common theme is friendship development. Since kita and bocchi are often characters in a story, their friendship might be explored in depth, showing how they get to know each other better over time.
I'm not sure specifically what the'mari secret story' is as it could be something very unique or personal. It might be a story related to a person named Mari that has some secrets within it.
Well, 'ben mari fanfic' might be a work of fan - created fiction involving characters named Ben and Mari. It could be set in a particular fictional universe, like a fantasy world where they have to go on quests together, or it could be a more down - to - earth story about their friendship or love story in a modern - day setting. There's also a possibility that it's a part of a larger fandom and the story could be influenced by the overall themes and ideas of that fandom.
I'm not aware of a specific work titled exactly 'isekai ni kita novel' being extremely popular. But there are many popular isekai novels in general, like 'Sword Art Online' which has some elements of being transported to a different world.
Since I don't have detailed information on 'orenchi ni kita onna light novel', it might be about a female character's journey in a fictional world. Maybe it involves her facing challenges, meeting new people, and experiencing different emotions. It could also have elements of mystery, love, or self - discovery depending on the genre of the light novel.