Many characters from Zoophobia have this. Most notably Alanzo, Jack, Spam and Zill. And boy are they expressive- each character's Big Ol' Eyebrows convey a different state of mind (smug, ecstatic, anxious, etc).
Minmax being bald, his only "facial hair" is his bushy black eyebrows, making them very noticeable. To the point where out of all of his "Maze of Many" incarnations, the eyebrows are the one thing that remain consistent.
Forgath has technically even bigger eyebrows than Minmax, but his dwarf beard make it less obvious. One alternate Forgath pushes this into a whole obsessive level.
Many characters from Every Button Hurts the Other Guy have large eyebrows, but Shota and Russel go as far as having the classic, thick, black rectangles, and Russel doesn't even have black hair.
In Russel's case this is likely a parody of Ken Masters from Street Fighter, whose eyebrows are conspicuously a different colour than his hair.