Miku is depicted as a sixteen year-old girl with with long, turquoise twin-tails. She also wears what resembles to be a traditional school uniform with a turquoise tie.
Not much is known about her personality, due to being dead in We Killed Miku! for most of the episode, though it seems that she takes her job as a singer very seriously. In the official description, it is difficult to define her personality due to the fact that she sings the widest range of songs.
Miku is killed by Mario as part of setting a trap to kill SMG4. The two do not realize that it is Miku until the intentions are revealed by Dr. Mario. SMG4 and Mario then try everything, from magic to science to revive her, but nothing works until she is revived by a 1-Up Mushroom, to which she wonders how she got to the concert. Upon being called, she goes to the stage and sings Tell Your World to the audience, which ends the blooper.