Reina has always had feelings for a senior who lives nearby, and her feelings for him remain unwavering, and she joins the company where he works. However, he gets a girlfriend... Reina, who has feelings that she has nowhere to go, is asked by his senior for advice on sex with his girlfriend. "...Then why don't you try practicing with me?" Reina feels a fleeting joy of being intimate with the person she loves, no matter what the reason... This is a naughty love story in which a secret practice brings two people closer together.