Saiko
- Primary work
- Cool Shock B.T.
- Occupation
- Security Guard↗
Saiko (西戸) is one of the main antagonists of the Cool Shock B.T. series, specifically appearing in the fifth chapter, " The Dinosaur Fossil Theft Incident."
He is a violent and sadistic security guard working at the department store hosting the Great Dinosaur Fossil Exhibition. He pursues B.T. and Koichi Mugikari when they attempt to steal a dinosaur skull.

Image attribution details
Saiko. Source illustration via JoJoWiki; copyright remains with the original rights holders.
Image via JoJoWiki. Original franchise/production rights holders retain copyright; the wiki text CC BY-SA license does not license this image.
Original image ↗ · Archived image ↗01Basic information
02Appearance
Saiko is a tall man with a muscular build. He has thick dark hair that curls at the nape of his neck, very thick eyebrows, a prominent nose, and a square jaw.↗
He wears a standard security guard uniform consisting of a light-colored, long-sleeved button-up shirt, a dark tie, dark trousers, and a peaked uniform cap. He wears a name badge on his left breast pocket that reads "Security Guard Saiko" (警備員 西戸, Keibi-in Saiko).↗
03Personality
Saiko is a cruel and sadistic man who abuses his authority. He proudly refers to himself as the ruler behind the scenes of the department store. He takes pleasure in tormenting anyone who misbehaves; when he catches Koichi Mugikari trespassing in the daytime, he violently twists the boy's arm and playfully threatens to rip it off. He also displays repulsive behavior as a form of intimidation, such as showing Koichi a piece of gum on his tongue, taking it out and making a ball, comparing it to fecal plugs that bears make before hibernating, and then even threatening to do that to Koichi.↗↗
Despite his physical strength and cruelty, Saiko is scientifically ignorant and highly gullible. When B.T. completely fabricates a chemical reaction using complex-sounding fake chemicals, Saiko falls for the bluff instantly. Terrified of being melted by imaginary acid, the previously imposing guard drops to his knees and begs the children for mercy.↗↗
04Story
SPOILERS
Cool Shock B.T.
Saiko is a security guard patrolling a department store that is hosting the Great Dinosaur Fossil Exhibition. During the day, B.T. pulls Koichi Mugikari into a restricted storage room. B.T. gets into a box and plans on hiding there until night so they can steal the skull of a spinosaurus, but Koichi is too late to hide when Saiko appears inside the room. Saiko arrogantly declares himself as the ruler behind the scenes of the department store.↗
Around 7:30 PM, Saiko is on night duty when B.T. and Koichi successfully manage to detach the spinosaurus's skull using pliers. However, the phone in the exhibition room rings so the pair hides behind a desk, leaving the skull on the ground. Saiko enters the room and answers the call from his branch manager, who warns him that he received a call that thieves have infiltrated the building. Saiko arrogantly laughs it off as someone's prank call.↗
He notices the skull on the ground but ignores it before leaving the room. When Koichi gets up to grab the pliers, he bumps into a container holding a fossilized hand, which falls onto the ground and shatters. Saiko returns from the noise and immediately attacks Koichi, whipping his iron chain and making a mess. B.T. grabs a nearby fire extinguisher and sprays the foam directly into Saiko's face, temporarily blinding him. While Saiko screams in pain, B.T.↗
Eventually, Saiko manages to break down the door by pulling the handle off. Covered in dried foam, an enraged Saiko tracks the boys down and corners them once again. He knocks Koichi over and strangles him using his chain. In revenge, B.T. pulls out a can of hairspray and aims it at Saiko. B.T.↗
Saiko initially claims that B.T. is lying, but B.T. starts counting down from three. Terrified by the threat of being melted, Saiko immediately drops his chain and begs B.T. to stay away. He promises not to follow B.T. and Koichi anymore. Just in case, B.T. gets Koichi to tie up Saiko's hands and feet with rope, leaving him behind as they flee the store.↗↗
05Plot details
SPOILERS
Profile details
Status Status based on their final appearance in the part(s) they are featured in: Alive↗
06Sources & attribution
- Saiko
Source bibliography (1)
- Cool Shock B.T. Chapter 5: The Dinosaur Fossil Theft Incident Open ↗
07More profiles to explore
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