|Toenail of Satan|
|Family and Relations||Unknown|
Toenail of Satan is the main villain of the Kekko Kamen franchise, acting as the principal of Sparta Academy and issuing the harsh punishments to students who don't meet the academy's strict criteria. He always attempts to find out Kekko Kamen's secret identity but ends up failing most of the time. He was also known for breaking the fourth wall a couple of times.
Toenail of Satan has the appearance of the evil clown archetype wearing a white demonic mask and a jester hood.
Toenail of Satan is a perverted maniac obsessed with using women for his plans. He is not very bright either, planning on cutting women's top halves off without anesthesia in order to make them into mermaids.
Toenail of Satan appeared when Jun Hono was on vacation in her homeland of Okinawa. She along with several other young women were kidnapped by Toenail for his idotic plan of making them into mermaids by cutting them in half and attaching the top halves onto the lower bodies of dolphins he gathered. As the saw blades came close to a woman, Jun managed to power down the women's cell and send an SOS to the Mazinger Angels. Using a couple of power rods as Nunchaku, Jun pursues to fight against Toenail of Satan before escaping his submarine as it exploded.