The short manga is titled Slow Damage ~Zenjitsutan~ (Slow Damage: Prequel).
The official website for the Nitro+CHiRAL boys-love game brand’s upcoming adult game Slow Damage revealed on Wednesday that the game is getting a short prequel manga adaptation by Sumimoto in summer 2020.
Nitro+CHiRAL’s Sweet Pool game launched in 2008 and inspired a manga in 2010, which Viz Media digitally released in English.
Nitro+CHiRAL’s DRAMAtical Murder adult visual novel debuted in 2012, and it inspired a manga in 2012 and an anime in 2014.