Hakaiju

A chilling 12-issue horror manga from Tonkam (2011–2015), Hakaiju traps a group of high school students in a quarantined facility where a grotesque, plant-like monster transforms its victims into brutal, fungal hybrids. Driven by visceral survival horror and body horror, the series is best known for its unrelenting tension and the cruel, desperate choices forced upon its young cast. It stands as a stark, self-contained example of the "closed circle" horror subgenre in manga, where no one is safe and the monster is as much a product of the environment as it is a threat.