Keikenzumi na Kimi to, Keiken Zero na Ore ga, Otsukiai suru Hanashi.

Ryuuto Kashima is a gloomy high school student. Because of a punishment game, he was forced to confess to Runa Shirakawa, a girl from the top of school caste and admired by everyone. They ended up going out for the unexpected reason of "Err, I'm free now so..." but, Ryuuto ends up following and eavesdropping Runa getting confessed by a handsome soccer club member, and Runa bringing Ryuuto, whom she just started dating, to her own room as a matter of course. They have different friends and ways to have fun, different in just about everything. And yet, surprised by their differences everyday, accepting it, they begin to relate with each other. A love story that will make you feel wonderful when you read it, starts now!

(Source: Kadokawa, translated)