The Yurei is a type of Japanese angry spirit and are known to inhabit the Aokigahara Forest.
After Janine Melnitz and Kylie Griffin were teleported to Tokyo by Proteus, they went to the Embassy of the United States in Tokyo. The employee who worked with them noted this was rather irregular but promised to get them back home as soon the embassy could. She revealed the Japanese government wanted to make sure none of the local ghosts were angered by the incident. Janine agreed and promised to send someone to help clean up any possible problems. She was eager to get home. Nobody noticed the Yurei in the office's mirror.
Kylie Griffin and the Chicago Ghostbusters ventured into Aokigahara with a local guide in search of the Map to Nikulausson's Tomb. Kylie preferred not to antagonize any of the ghosts in the forest but a female Yurei appeared to Dani Shpak and Lou Kamaka. They opened fire and blasted part of her face off. She only laughed. Soon, more ghosts appeared and surrounded the Ghostbusters. Kylie didn't think they had the resources to deal with all of the Yurei but Ron Alexander revealed his Boson Caster and the Chicago Ghostbusters' throwers had the capability to fire a refined atomizing stream. Ron, Dani, and Lou "distracted" the ghosts while Kylie, Rookie, and guide broke off to find the map.
- Erik Burnham wrote the Yurei scene simply as a fun gag to end the comic with. 
- Aokigahara is infamous for being infested with Yurei, angry ghosts said to manifest from those who kill themselves in the forest as it a notorious location for committing suicide.