Ame ga Futtara, Kimi to Kiss wo
雨が降ったら、君とキスを · あめ が ふったら きみ と きす お
est. Rough estimate based on volume count, reprints and magazine — not an official figure
Overview
Note: Includes one extra chapter.
Source: AniList
External databases: AniList
How to compare editions, collected volumes and ISBNs / Sources, updates and corrections