The unnamed protagonist of the game is the son of Kekko Kamen's arch enemy, Satan's Toenail (サタンの足の爪). He is recruited by his uncle, Satan's Rump (サタンの尻), who is the principal of the school to help him sadistically punish the students.
Unfortunately for them, Kekko Kamen shows up to thwarts these actions at nearly every turn. The protagonist makes several attempts to locate and capture the heroic antagonist, recruiting the help of other individuals like the school janitor or a Sherlock Holmes knockoff, but they all end in failure. It is in the final arc of the game that the "Fella Senshi" step in. Which senshi appear depends on how many girls were interrogated by the player. If it is around three, Mercury shows up. If it is around six, both Mercury and Mars show up. If all possible girls are interrogated, Mercury, Mars and Moon appear.Sent by Satan's Toenail to give assistance, they school the protagonist; telling him that the reason he has crashed and burned up until now, is that he and the other men were distracted by Kekko Kamen's nudity. As a females themselves, they confidently reason that such charms would have no affect. The villains capture and rape a female student to bait their opponent. It works, and another battle is waged, though as predicted by Mercury, this time Kekko Kamen loses.
The protagonists unmask and torture the vigilante outside of the school, but are soon interrupted by multiple other Kekko Kamens who proceed to beat them to a pulp. Toenail's son manages to survive. As for the senshi, however, they are not so fortunate.