I Don't Like Sundays
日曜日なんか大嫌い · にちようび なんか だいきらい
est. Rough estimate based on volume count, reprints and magazine — not an official figure
Overview
A collection of oneshots including "I Say a Little Prayer": Kiyoko is in a bar one day, drowning her sorrows, when she runs into a girl who used to have a crush on her in school, Ayumi. They end up hooking up. Kiyoko knows she's gay, but Ayumi has never been with another woman before. Will they manage to work things out? (Source: Lilicious)
Source: AniList
External databases: MADB · AniList
How to compare editions, collected volumes and ISBNs / Sources, updates and corrections