Hanabatake to Wakarebanashi
花畑と別れ話 · はなばたけ と わかればなし
est. Rough estimate based on volume count, reprints and magazine — not an official figure
Overview
Takuya, Yuiji, and Aki are childhood friends who have always been together. Takuya secretly likes Aki, but she suddenly gets a boyfriend. Takuya nurses his broken heart with Yuiji, who suddenly confesses that he's always liked Takuya. (Source: Enterbrain)
Source: AniList
External databases: MADB · AniList
How to compare editions, collected volumes and ISBNs / Sources, updates and corrections