Gender: Male
Age: 18
Height: 179 cm
Blood Type: O
Occupation: Unemployed
Hometown: Saitama
Status: Deceased
BIM Type: Blazing gas
Kill(s): 0

Mitsuo was a very large man. In the beginning he travelled along with Himiko, Masashi Miyamoto and Isamu Kondō.

After Isamu Kondō was killed by Masashi Miyamoto, he along with Himiko ran away from Miyamoto taking away his supplies. He teaches Himiko how to use the radar to track people. He was killed by Himiko while attempting to sexually assault her.

Not much is known about his past, only that he had sex with a girl he liked once, and that afterwards everybody at his school hated him (implying that it may have been rape, a fact he seems to be unaware of). This could lead to him being sent to the island.