mikudayo is a derivative character created in the image of hatsune miku. she is a human-size mascot costume based off of the hatsune miku nendoroid, how ever the costume was clumsy and awkward. she first appeared in 2011 in "Tokyo Game Show 2011", where she was promoting project mirai, however mikudayo scared the children there. mikudayos name was officially recognised in apr 2012, and mikudayo herself became an official member of the cfm line up on 24 sep 2012. she is often depicted as evil in the fandom. the fanloid fandom wiki says mikudayo first appeared on 11 sep 2011, however the vocaloid fandom wiki says it was 17 sep 2011. a youtube video uploaded on 19 sep 2011 by rlgofs (https://www.youtube.com/watch?v=OP7BPyfTLOA) says it was 18 sep 2011, and i could see the difference between the 17th and 18th being just time zones, so ive chosen to go with the 17th.
mikudayo has gotten multiple art exhibitions, including one in yokohama which features the art of cha_bo (cha_bo39 on twt). this was held in 2016 from 1 may to 8 may at the Hachiban-kan venue in Naka-ku. https://www.youtube.com/watch?v=hUDQC7qOX5Y here is a video showing it in more detail. much of the art is creepy and horror-like, and shows mikudayos creepiness