BT21 is a popular line of characters created in collaboration with the South Korean boy band BTS and the global character brand LINE Friends. Each character represents a unique personality and was designed by the members of BTS, making them relatable to fans. The characters include Tata, Cooky, Chimmy, Koya, RJ, Shooky, Mang, and Van. Launched in 2017, BT21 has expanded into various merchandise, including plush toys, clothing, and accessories. The characters have gained a significant following worldwide, appealing to both BTS fans and those who enjoy cute and creative designs.