These were characters originally designed in 1982 used on a variety of products for young children including candy, diapers, backpacks, school supplies, and books. I will be concentrating on the color-change Kawarinko (かわりんこ) toys from Agatsuma Iアガツマ) shown below. ¥1,280 each.
Grape the Mouse (ネズミのグレープ) turns orange in water.
Pie the Cat (ネコのパイ) turns yellow in water.
Cookie the Bunny (ウサギのクッキー) turns white in water.
Cherry the Bear (クマのチエリ) turns blue in water.
Candy the Squirrel (リスのキャンディー) turns green in water.
Apple the Dog (イヌのアップル) turns pink
Pinocchio Bath Toy Series (ピノチオのバストイ シリーズ):
These do not appear to be flocked like the above ones.
Cookie the Bunny (ウサギのクッキー)
Apple the Dog (イヌのアップル)
Pie the Cat (ネコのパイ)
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