•About this Yokai: A person clad in bandages all over like a mummy, appears riding a bike at twilight. slowly, but cheerily sings: "Ton, Ton, Tonkaraton!! ♪" When they encounter someone, their demeanour changes from happy go lucky to dead serious, unsheathes a katana & demands that you “say Tonkaraton!!"
• If you comply & say "Tonkaraton" he leaves.
• if you do NOT say "Tonkaraton" he slays you with his sword.
• if you react and say "Tonkeraton" too early, before he can says "say Tonkeraton" first, you'll also be cut down. ( only Tonkeraton can say when someone can say Tonkeraton!! )
• if the person is too frightened to speak or if they mumble, he will command that you "Say it again!”
Those who are cut down by Tonkaraton soon find themselves growing bandages all over and find themselves turning into another Tonkaraton. - For that reason, they are often said to attack in groups. - Attacks are most likely to happen towards twilight or nightfall. There are also variations to the story where you take his place as the tonkeraton, in other words there can only be one. (it’s unclear which is true 🤷♀️) it’s also said that wearing a bandage over your left hand will fool him.
• History & Origins: Another Yokai of the early 90s, This yokai has since allegedly been sighted all over the country. - The Legend about this one seems to stem from the 1994 cartoon: "Gakkou No Kowai Uwasa: Hanako San Ga Kita!!" - ["学校のコワイうわさ 花子さんがきた!!"] - [you can watch the Tonkaraton segment from episode 10 here.] -
The show's staff were later interviewed and asked if it was an "original story", they said that it originated as an urban legend from the hometown of one of the creators, but they didn't know the details, and no further explanation was ever given. - So, The truth of the story's origin is seemingly unknown & often debated because the show adapted various urban legends from around japan, and with time, naturally, it spread.
[Tonkeraton as it appears in the segment]
Tonkeraton also more recently appeared on the Urban Legend Documentary show "口を揃えた怖い話" "Scary stories with a mouth"  contributing to his recent popularity and inclusion in various modern yokai bestiaries & media.
[as he appers on scarystories with a mouth]
• Similar Yokai: This yokai follows the "Kashima-Reiko" multiple-choice, "Do X, but Dont do Y, and you'll be OK" trend which was very popular among the 70s, 80s & 90s yokai & urban legends from time. . Researchers say that if its true that it originated as an urban legend, it's quite likely a derivative of the "wounded soldier" & other male variants of the Kashima-san legend. By extension,the story uses similar tropes as the "Shichinin Misaki." (the ghosts of seven samurai who must add one to their ranks before they can pass on.) He’s also visually quite similar to "Headless Bikers" which date back to at least the '70s. (Admittedly that’s mostly because of the bike.)
See also: Hanako-san, Kuchesake-onna, Teketeke, Headless Bikers, Sinchin Misaki.