There used to be a boy who could control Youkai with a mysterious watch. However, he became unable to see Youkai when he became an adult. With the boy's duties finished, the watch was buried away in space-time. Then 30 years later, quiet everyday life comes to an end as a fateful day beginning with a comet drawing near. The terrible Youkai virus Onimaro infects people's malevolent intentions and spreads infinitely. The one chosen by the Youkai Watch is the one who can save humanity from its crisis. The bond between humans and Youkai may be recovered with the attainment of a new Youkai Watch.
When Keita frees Whisper, a ghost-like youkai, from 190 years of imprisonment, Whisper pledges to protect Keita from supernatural dangers. Whisper also gives Keita a watch that allows Keita to see other youkai. Together with the twin-tailed cat spirit Jibanyan, they encounter many youkai-related problems and solve them.
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Official Release:
- English Asia release by Shogakukan Asia - Singapore
- English North America release by Viz Media
- Indonesian release by Elex Media
- Spanish release by Norma Editorial
- Latin-American release by Panini
Taking place after the events of the fourth film, the series centers on Keisuke Amano, Natsume's brother who doesn't believe in supernatural phenomena. But as he notices his sister is frequently comes back home late, he decided to stalk her, only to find out she is exorcising evil Yo-kai and running a Yo-kai detective agency. With their secret revealed to him, Natsume decided to let him tag along in her activities as they investigate Yo-kai crimes and take on evil Yo-kai to maintain peace all over the city.