Eiko is pushing thirty, but has never once had a boyfriend. She's always been fully contented with living the single life and immersing herself in her passion for video games...that is, until she met Koigakubo-kun, her extroverted younger coworker who's got a silver tongue. After a night of drunken connection, he ends up becoming her romance guru! But as their lessons progress, they start to fall for each other. Koigakubo-kun professes his feelings for her, and before she knows it, they're a couple. But things start getting a little rocky after Eiko grapples with a comment she overhears at a house party about her putting too much pressure on Koigakubo-kun. Anxious and desperate to give him whatever space he might need, Eiko starts behaving strangely...and Koigakubo-kun grows suspicious.