Ruby Red wo Kamikudaku
ルビーレッドを噛み砕く · るびー れっど お かみくだく
est. Rough estimate based on volume count, reprints and magazine — not an official figure
Overview
I want to be "special" to my sensei. Akane is an Omega who can see people's pheromones as multicolored "crystals”. During his school days, when he was lonely because of his peculiar constitution, he meets Makise, a school nurse teacher. 5 years later, they are miraculously reunited, but Makise has a secret...? (Source: Libre, translated) Note: Includes one extra chapter.
Source: AniList
External databases: AniList
How to compare editions, collected volumes and ISBNs / Sources, updates and corrections