Review Detail of iknowu in Reborn in Genshin Impact with System

I don't get it there is no review but 2m reading. It's a Genshin Fanfic but a fan fiction writer says "This fanfiction will only be posted on my pa-treon just $7 to join"... Is this even legal? If I remember correctly it should be illegal. I'm sorry but i can only give 1 star something like this!