Hatsune Miku (or just Miku) is a minor character in the SMG4 series.
She is a culturally popular Japanese vocaloid developed by Crypton Future Media who came into play initially on August 31, 2007, and with stability on August 31, 2016. She is depicted as a sixteen year-old girl with with long, turquoise twintails. In the real world, Miku is partially responsible for the success of the Vocaloid series.
Miku's name comes from merging the Japanese words for first (初 hatsu), sound (音 ne) and future (ミク miku), thus meaning "the first sound from the future".
This is referring to her position as the first of Crypton's "Character Vocal Series."
Miku is voiced by Japanese voice actress Saki Fujita.
Although appearing mainly as a 2D character in the background, she has made a few appearances as a GMod model.
Ssenmodnar 7 is the only video to feature her singing one her songs, which is ぽっぴっぽー (PoPiPo), or in English, Vegetable Juice. This is observed during the last skit of the episode, where Dr. Eggman is seen rocking Dance Dance Revolution while Mario and Sonic watch on.