The mascot of the Megami Tensei series of JRPGs created by Atlus, Jack Frost is a demon based off a personification given to ice, snow, and winter. His personality is generally shown as rather jovial, impulsive, and at times violent.

His current design is a white, round, humanoid body with minimal blue clothing, including a hat with horns and a smiley face on top. His very original design looks more like a snowman with a hat, cane, and scarf, though this design is rarely used nowadays.

He has ended up in a majority of Megami Tensei games, as well as spin-offs and unrelated series as a cameo.

There are multiple other demons in Megami Tensei games with designs based off of Jack Frost, such as Jack-o'-Lantern (formerly Pyro Jack) and Black Frost.