No offense and completely not siding with anyone on this; but on that ban report, I find a sick twist of irony in that RHia's picture is from Majora's Mask...or OoT...
On topic: The Happy Mask Salesman appears in both Ocarina of Time and Majora's Mask, but plays a far bigger role in the story of Majora's Mask. The image in question is official artwork for Majora's Mask, to confirm.