Itsuka Tomodachi ja Nakunaru to Shitemo
いつか友達じゃなくなるとしても · いつか ともだち じゃ なくなる と しても
est. Rough estimate based on volume count, reprints and magazine — not an official figure
Overview
Two best friends learn to love one another. Tomo has trouble keeping his feelings for Shuuhei under wraps because he doesn't want to ruin the friendship they have. Meanwhile, Shuuhei is doing his best to not to worry Tomo and make him cry. (Source: Hakusensha, translated) Note: Includes one extra chapter.
Source: AniList
External databases: MADB · AniList
How to compare editions, collected volumes and ISBNs / Sources, updates and corrections