Mugen Puchipuchi

Mugen Puchipuchi (∞プチプチ^?) is a Japanese bubble wrap keychain toy by Bandai (Asovision). Mugen means infinite in Japanese while puchipuchi means bubble wrap and also refers to the sound of the bubbles being popped. The toy is designed to mimic the sensation of popping bubble wrap for infinite number of times. It is made of a double layer structure of silicone rubber to create a similar feeling to the real bubble wrap. The square shaped toy has eight “bubbles” that would make a popping sound when pressed. It would also make a sound effect for every 100 pops, which includes “door chime”, “barking dog”, “fart”, and “sexy voice”. Bandai worked with the Puchipuchi bubble wrap company to create a design that is most realistic to the real bubble wrap. Bandai also created other Mugen keychain toys based on Mugen Puchipuchi, such as Puchi Moe, Mugen Edamame, and Mugen Periperi. The original Mugen Puchipuchi has also been marketed in North America as "Mugen Pop-Pop".

Puchi Moe is the anime themed version, which is similar to the original Mugen Puchipuchi. Instead of random sound effects that come out when pressed, it includes an anime character voice. There are four different types, each based on an anime character : childhood friend, French maid, tsundere, or younger sister.

Puchi Moe is created more for the lucrative market of otaku. All four character voices are done by voice actress Rie Kugimiya.

Mugen Edamame (∞(むげん)エダマメ, Infinite Soybeans^?) has beans inside a pod that appears like an edamame or baby soybean. When the beans are pushed, each one pops out individually showing one of the twelve expressions or faces, which are pre-set and randomly packaged. Unlike the original Mugen Puchipuchi, it does not create a sound when pushed.

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Wikipedia