Series goes like this (chronological order)
0. Aazami - past Yumi x Kan
1. Sabita Yoru Demo Koi Wa Sasayaku -Yumi meets Mayama and breaks up with Kan chan
2. Renai-rubi no Tadashii Furikata (ch3.1 - 3.5) - Kan meets Shuuna and turns uke
- Narrow (Place collection) - dj Kan x Shuuna smutty sidestory
3. Hadakeru Kaibutsu - continuation Kan x Shuuna (Shuuna's POV as far, timeline parallel to no.2 for ch1)
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Personal opinion - best reading order 1, 0, 2, 3
Azami