The Kirie Sakurame Nekomens Acrylic Charm will be released in Japan in March 2018 by ACG. Nekomens is a line that turns creates a neko/cat design for characters.
This charm will be released as merchandise for the UQ Holder! anime that aired in the fall season of 2017. It is made of an acrylic material and included on the clasp is an earphone jack plug.
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