After my hands and legs were tied in a cross-shaped position, I was tickled from behind, including my back and nipples. While tickling my nipples, my sides were also tickled at the same time, making me feel confused between the naughty feeling and the tickling. Mio-chan feels like she's laughing and writhing even though she's going limp. The way it breaks apart is so cute, so please take a look.
