Kagamine Rin and Kagamine Len are virtual singers created by Crypton Future Media as part of the Vocaloid software series. Released in 2007, they are designed to produce singing by synthesizing human voice samples. Rin is characterized by her energetic and cheerful personality, while Len is often portrayed as more laid-back and gentle. Both characters are depicted as twin siblings, with Rin typically represented in a yellow and black outfit, and Len in a similar style with blue accents. They have gained popularity in the Vocaloid community, inspiring numerous songs, fan art, and collaborations across various media platforms.