Sans

Lazy, playful, but at the same time can be a serious skeleton.

Face: A permanent smile always shines on his skull, and white pupils glow in his black eye sockets. They disappear when he becomes serious or angry. Eye in combat: When attacking or using telekinesis, the right pupil disappears, and the left iris lights up, flashing blue and yellow.

Gait: He is only about 150 cm tall, and his dialogue font (Comic Sans) always has lowercase letters.

Top: An unbuttoned blue jacket (or hoodie) with a hood, worn over a simple white t-shirt or sweater. Official merchandise often features the jacket with fluffy white fur on the hood.

Bottoms: Black (or dark blue) athletic shorts with vertical white stripes on the sides.

Shoes: Slippers. Their color isn't specified in the game itself due to the pixelated graphics, but in the official Super Smash Bros. game (where Sans appears as a costume) and on collectible figures, they're pink.