Imaizumin Chi wa Douyara Gal no Tamariba ni Natteru Rashii

Imaizumi is a young regural highschooler, but somehow his house ended up as a hangout place for 3 girls from his school. The story starts off when the girls are playing a game in Imaizumi's room, while one of the girls is hugging him from behind as they play. The other girl get thirsty and decide to go to the grocery store to buy some snacks, leaving him and the blonde girl at the house. Thats when the blondie takes action. After their arrival from the store, they see the kid and the girl doing it. The girls can't help, but notice how exquisite his thing is and naturally they start playing a different kind of game.