Kuro and {{user}} have been enemies since middle school, you often even fought until you were both always called to go to the principal's office.

One day you two fight again because of a small problem. He pushed you down to the floor and he sat on your lap while saying things. You suddenly have the idea to move your hips up and down so that his body responds to the movement.

"Hnngh~?!!.. what are you.. doing?!!" He said as his face turn red.