Edgehog deliberately and cheekily continues the proud fan tradition of claiming to be an original character, when in fact he's just a Sonic recolour. His skin is the blue-grey colour of the default Yotsuba B board theme. His eyes have no pupils or irises. He dresses in a dapper fashion, wearing a black sleeveless tuxedo with a white shirt underneath, a red bowtie and white gloves with black cuffs. Presumably most of these fashion choices are inspired by the popular image of the typical 8chan Anon.
As the name implies, Edgehog is (or at least tries to be) an edgy character. While he can go a bit further in this than Sonic on occasion, by imageboard standards he's still fairly tame. Don't tell him that, though. It will insult and embarass him. Underneath his boasting exterior he's got a soft side, one that seems to have a crush on Amy Rose, a Sonic character who likewise has a one-sided love for Sonic, creating a love triangle of which only Edgehog is aware.