The whole plot of the manga is about a high school girl wanting her Oji-san to teach her "bad things". Every chapter basically follows the idea of subverting the expectations of the reader the moment they read the first panel.
Though common, the subversion gimmick gets old fast.
So for the story, its a 5/10. It's not something new, and it's not something to write home about. Regardless, the relationship between the MC and the Oji-san is wholesome, to some degree.
Art: 8/10
Art style is good, can't complain. Ayumu is adroable and her expressions and how she's drawn is cute. Same goes for the Oji-san. The art style helps in showing the reader that this is a light-hearted manga.
Character: 6/10
Character roster is somewhat short, but memorable. I'd give it a 6, based on how they could've gotten more appearances in the manga.
Enjoyment: 7/10
Solid 7. Depends on how you view it, it's a light-hearted manga about a girl and her Oji-san. Everything is implied just to subvert the reader but like what I said, it gets old. Though their antics are fun to read.
Overall, a 6/10 manga.
