The power to eat massive quantities of food to no ill effect.
The user can eat massive quantities of food at once to no ill effect, this can extend into versions of Matter Ingestion. This power can be very useful, especially for those that possess an abnormal nature. Because of this, nutritional intake needs are a great deal higher than that of normal, requiring more food in order to keep their strength up.
Due to his usage of a prototype stealth camo, the Fear (Metal Gear Solid 3: Snake Eater) is constantly hungry and must eat regularly.
Yoshi (Super Mario), like all members of his species, has a bottomless belly and can eat virtually anything.
Jewelry Bonney (One Piece) was known as "Big Eater".
Wapol (One Piece) eats pretty much anything at unlimited amounts, even a knife.
Many D. Family members (One Piece) are shown to have big appetites.
"Big Mom" Charlotte Linlin’s (One Piece) love for sweets gives her a destructive eating disorder. Every once in a while, she'll start to rampage in search of what she wants to eat. In this state, she will destroy everything in her path, even her own children.
Castiel (Supernatural) has eaten burgers numbering in the "low hundreds" without signs of slowing down while under the influence of Famine.
Taiga Kagami (Kuroko no Basket) is a glutton and is able to eat at least five times a normal meal.
Lilotto (Bleach) using "The Glutton" to eat the Soul Reapers.
Aaroniero Arruruerie (Bleach) using "Glutoneria" to eat Hollows.
The Fang Gang (Mixels)
Glutton (Valkyrie Crusade)
Gluttony (Fullmetal Alchemist: Brotherhood) lives up to his name.
Shaggy Rogers & Scooby Doo (Scooby Doo Franchise) are textbook users of this ability.
Big Billy (The Powerpuff Girls) of the Gangreen Gang
America (Axis Powers Hetalia)
Mr. Luggs (Luigi's Mansion) is a gluttonous ghost who prefers all-you-can-eat buffets rather than simply three meals a day. It is said he even ate himself to death and still wasn't satisfied.
Mamodo (Zatch Bell!) have much greater appetites than humans. Their favorite food is fish.
Jughead Jones (Archie Comics)
Gourmands (Ben 10) have pocket dimensions for stomachs, allowing them to ingest virtually anything and of any quantity, they can even devour entire planets!
Mr. Creosote (Monty Python) is infamous for being able to eat amounts of food beyond the limit of normal humans, usually vomiting the excess amount of food later on.
Amethyst (Steven Universe), as a gem, does not need to eat. Because of this, she can eat as much as she wants - whether any of it is edible or not - with little to no ill effects.