Sadistic-Senpai-Loves-2-Offend's manga / #Fluff(18)

Author kept it light even though the subject matter is dark: human-body modification, human experimentation, dehumanization, etc. Psychological manga which had potential to be dark, heartbreaking, messed up one but if mangaka kept it light, cute, fluffy romance with darkness lurking behind(adding psychological factor), that works well too. Hope so somebody completes the translation of all volumes. Good read.