PowerFX base their Vocaloids on classic cult monsters of horror and science ficiton such as Frankenstein's monster. Sweet ANN is based on the "Bride of Frankenstein" and Big Al the monster himself. Oliver was also intended to be a Frankenstain monster, but the artist decided stitches didn't suit him, so he chose bandages instead to cover his face.
However, the artist did note that they were open to interpretation. In Japan due to the difference in culture, they referred to Oliver as "Moe bandage boy" (包帯萌え少年), because moe style art was their closet interpretation of the bandages. Some view him as a zombie and others think of him as a very loose interpretation of a mummy monster. The bandages give way to a lot of pondering as to what they cover. Some think an injury, some think robotic parts, some think it's just something he wears.