Hananoi-kun to Koi no Yamai花野井くんと恋の病 ; 花野井君的相思病 ; I'm addicted to you

Hananoi is the most coveted boy at his class. Handsome, intelligent and mysteriously aloof, no girl is beyond his reach. In a fated winter day, his classmate Hinase Hotaru witnesses him callously breaking up with his girlfriend, who storms out of the caf they're in after throwing her drink on his face. Later in the day, Hotaru finds him at a park bench with an empty stare, idling under the snow. Concerned, she offers him cover under her umbrella. The next day, Hananoi asks her to be his girlfriend and she says no. However, Hananoi doesn't give up. Why did this mere act of kindness reach someone like Hananoi? Why does it have to be Hotaru? Does she have what it takes for him to lift up the barriers he has for everyone?