Tohoku Zunko (東北ずん子) is a Japanese VOCALOID developed and distributed by AH-Software Co. Ltd., and was created in collaboration with SSS LLC.. She was released in June 2014 for the VOCALOID3 engine. She is also sold as a VOICEROID+. An update to the VOCALOID4 engine was released in October 2016.[2] Her voice is provided by the Japanese voice actress, singer, and narrator, Satomi Satō (佐藤聡美; Satō Satomi), who is known for her role as Ritsu Tainaka from the Japanese music anime "K-ON!".[3]