Unfairy is noticeably shorter than the other Wicked Executives. He has a pudgy body with gray-white skin, thin arms and short legs, and two fuchsia dot-like eyes with buckteeth, as well as two horn-like protusions on top of his head. Like most of his colleagues, he has the same color scheme of clothing as them, in particular his being an oriental top colored dark purple with milky pink linings and the trademark hot colored Wicked flame in the center. He also wears milky pink wristbands.
He was stronger than them but they got to sap his strength and stall long enough for Nate to get enough strength to beat him. After he is beaten and returned to Dedtime, he was thought of as weak and got sent away.
His Japanese name, "Yakkai", can be also written as "厄介", meaning "awkward". His English name, "Unfairy", is a portmanteau of the words fairy and unfair, as it can easily outlast both Arachnus and Toadal Dude.
His Spanish name, "Injustio", is a corruption of "injusto" (Unfair).
His German name, "Nervo", is a corruption of "Nerv" (nerve; but also means annoying).