Ukuleleman is a tragic villain who appears in the anime, Space Dandy.
Ukuleleman is shown to be very obsessed with other people smiling, his obsession goes as far as willing to play a song of death that freezes people into a permanent smile and keep them as statues in looking for the perfect smile.
Ukueleman is lonely since he is the only member of his race and he was born into the world just to die alone without a smile,that is the fate of his race.
Ukuleleman was obsessed with Dandy since out of everyone he knew Dandy has the happiest smile and he wanted his smile as his own, thus he tried to steal Dandy's smile but failed. Dandy punched him and he bursts in flames, his mouth cracked and it appears that he died smiling.