1. Nothing is wrong with the concept. Just that all characters involved are either bland or unlikable.
2. If it is the latter, this story would had long been taken down. The story takes place in Alt ancient China. Literally with two layers of denial.
Skimmed until ch14. Meaningless interactions, fillers, and unclear focus. I thought it would be gritty or something, then he gets a yang body and nose ability to smell menstruation...
From the way mc interracts with his late brother's wife and maid, the author probably has a netori fetish. It's also convenient that the wife (always?) refuses her husband from entering her room