Hare Nochi Shiki-bu / Тёплое солнце и клуб «Времена года»

Haruno witnesses a mysterious guy crying under the sakura trees. He thought it strange, but who would have thought the guy turns out to be his classmate, Hitose?! Hitose declares that he's going to establish the "Four Seasons Club," with details of club activities being very unclear. But swept up in Hitose's vigor, Haruno joins the club by announcing, "I will be with you!"

(Source: Kadokawa, translated)