Toshiaki is one of the boys who reanimate deceased animals and make it counterproductive in Frankenweenie. Toshiaki is the tertiary antagonist of the film.
- Age: 12
- Birthday: August 20
- Hometown: New Holland
- Favorite Colors: Red, Green, and Blue
Toshiaki is over-achieving and mega-competitive. He is 12-years-old. He delights in beating Victor at his own game and like a power-hungry, mad scientist, Toshiaki will stop at nothing to win the top prize in the school’s science fair, even if it means using Victor’s ideas to do it. He also likes to say "i know"
- Toshiaki's character design may very well be a nod to the Japanese film producer Tomoyuki Tanaka; best known for the conceptualization and creation of famous movie monster and pop culture icon Godzilla.
- He was the one who created the Turtle Monster , in an attempt to bring his deceased turtle Shelley back from the grave. Shelley is an allusion to popularized Japanese movie monsters.
- He is the pitcher on the New Holland baseball team. Toshiaki prides himself on his baseball pitch; something Victor's father alludes to as team coach.
- After Shelley is zapped and reverted into her former dead self, Toshiaki picks up her shell sadly and says "Shelley?"
- Toshiaki is one of the kids Weird Girl's cat, Mr. Whiskers dreams about, the day he pitched the perfect game.
- Toshiaki is Bob's project partner; and the "brains to Bob's brawn." When they attempted to create a waterbottle jet, it ended with Bob falling off the roof and breaking his arm.