After Traveling Through the Apocalypse, He Had Sex with the Hero's Brother

Sheng Yu inexplicably traveled into an apocalyptic dungeon. Sheng Yu said that he would make peace with it as he came, so after digging through the dungeon, he finally found a person - Shen Ting, the male protagonist's younger brother. He survived until the end of the plot, so a system with unlimited supplies came to Shen Ting. After experiencing countless car rollovers, Sheng Yu could no longer cover his little vest. Looking at the man slowly approaching, he wanted to cry but had no tears. This was different from what he had promised (T^T). I originally thought it was an apocalyptic version, but in the end I found out it was actually a fairy tale? (Some people may think that this is an apocalyptic novel, but they find that this is not an apocalyptic novel in the traditional sense. Instead, it has more plot. Don't worry, it will be explained later. You can guess what it is like first!)