Sadly, I don't own too many of these treasured goods. In fact, I can only think of four examples at the moment: Detana!! TwinBee, Loopop Cube: Lup Salad, PoPoLoCrois Monogatari, and Rhythm Tengoku.
Four examples other than the one I'm discussing and highlighting in this very post, I mean.
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To my utter surprise, stuck inside the pages of the Hello Kitty World manual were the stickers you see here.
Truth be told, I'm a bit miffed this precious sticker sheet focuses entirely on Hello Kitty, aka Kitty White.
Granted, she's the star of the show--er, game--and this sheet only contains eight stickers, five of which are pretty darn small, so the lack of any Mimmy or Tippy stickers makes some sense.
Something that makes a lot less sense: none of these stickers directly refer to Hello Kitty World. (Erm, except the one at the top.) It's almost like Character Soft, the publisher of this Balloon Kid knockoff, just took a few existing Hello Kitty illustrations and slapped them onto the sheet you're ogling now.
All that said, I'd rather get a sticker sheet than not get one, so please don't take what I've written so far to be serious complaints.
See also: scans of the Detana!! TwinBee, Loopop Cube: Lup Salad, and Rhythm Tengoku sticker sheets