Synopsis

Takemiya Natsuki, a third year high school student is preparing for his university entrance exams. However, just before summer vacation begins, he is dumped by his girlfriend and receives nothing but E grades on his practice exams. Concerned, his older sister arranges for her boyfriend Kobayakawa Sota, who is also a student at the university she attends, to become his private tutor.

At first, Natsuki finds the overly cheerful Souta impossible to like, but whenever Souta unexpectedly shows a smile or innocently pats his head saying ‘You did really well!’, Natsuki can’t help but feel his heart skip a beat.
“There’s no way I could be falling for my sister’s boyfriend… So what is this feeling I’m having!?”