Six months ago, a colossal spiderweb emerged in the sky which attracted a lot of media attention initially. However, as time passed without any significant occurrence, people returned to their mundane routines and disregarded the web. Amedome Tsutsuji is one such individual who resides beneath the spiderweb and is often unnoticed by people around him. His classmates at school refer to him as "Ninja" for his ability to blend in seamlessly with his surroundings, even the automatic doors fail to detect him. Nevertheless, he possesses a unique talent to detect the incoming alien creatures descending from the spiderweb, who inhabit human bodies and prey on humans.
Consequently, Tsutsuji makes it his responsibility to keep a watchful eye over his crush, Mizuno, as she commutes from school. His approach may seem intrusive, but he only does so with her safety in mind. Tsutsuji joins forces with a friendly extraterrestrial named Tsuda and arms himself with a formidable weapon, a faucet. His objective is to shield Mizuno from the spider-aliens when they assault. Will Tsutsuji succeed in his mission to defend Mizuno from the spider-aliens with his trusty faucet?
