I haven't read this particular 'blow to katsuragi senran kagura fanfic' specifically. But generally, in fanfics related to Senran Kagura, they often explore the characters in more depth. Maybe this one focuses on Katsuragi and some kind of 'blow' could refer to an action, event or even a metaphorical concept within the story.
Well, 'senran kagura visual novel' focuses on the adventures of a group of shinobi girls. The visual novel aspect allows for in - depth exploration of their personalities, backstories, and the bonds they form with each other. The stories might include their struggles in the shinobi world, like facing off against rival groups, and also their personal growth in terms of skills and as individuals.
The plot might involve the male reader suspecting the girl of cheating. He could start noticing little things like her being secretive about where she goes or who she's with. As he digs deeper, he finds out she's been making deals with the enemy or flirting with other guys for some advantage. This could then cause a big rift between them and the male reader would have to figure out how to deal with this betrayal.
Well, you can start by looking on fanfic platforms like Archive of Our Own. Search for 'Senran Kagura x male reader' and then filter the results by rating and reviews. Some popular ones might have a well - developed plot that focuses on the relationship between the male reader character and the Senran Kagura characters in a non - inappropriate way, such as adventures they go on together or how they support each other in the Senran Kagura universe.
A possible fanfiction could be about a character from Naruto ending up in the world of Senran Kagura. Let's say Naruto himself gets transported there. He would be really confused at first by the different rules and the all - female cast (mostly). But then he starts to adapt and uses his shadow clone jutsu in creative ways during battles against the various enemies in the Senran Kagura world. He could also make friends with some of the characters and teach them about chakra.
Another theme is often the development of relationships. The male oc might form friendships, rivalries or even romantic relationships with the female characters. For example, in some fanfictions, he may start as an outsider but gradually build deep friendships with the girls through shared battles and experiences.