Lazy Sundae has the body of an ice cream sundae, having a white scoop with fudge and a wisp on the top, a chocolate brown moustache, and two brown wafer sticks with dull pink stripes. His lower part is a brown and white mix of ice cream in a glass cup in a wavy horizontal way. He has thin human-like arms and legs with the latter wearing brown socks and shoes.
As implied from his powers, Lazy Sundae is lazy and inactive to do anything.
Lazy Sundae's ability will make anyone be lazy on Sundays and do nothing on Sundays, no matter what they said the day before.