Pure Rubber Strap Sets are three sets of rubber straps that are based off the cast of the Riddle Story of Devil anime series. The straps were designed by illustrator Sunao Minakata and released by Japanese company PURE. The sets were released exclusively at Japanese Comic Markets.
The first set was released at Comic Market 88 (コミックマーケット88), which ran from August 14th to August 15th, 2015. The set consists of Haruki Sagae, Suzu Shuto, Shiena Kenmochi, Hitsugi Kirigaya, and Sumireko Hanabusa.
The second set was released at Comic Market 89 (コミックマーケット89), which ran from December 9th, 2015 to December 31st, 2015. The set consists of Shinya Banba, Mahiru Banba, Otoya Takechi, Chitaru Namatame, and Kouko Kaminaga.