Big Eater/Tabletop Games

Thin Characters

 * Shadowrun
 * At least in the first two editions, shamans of Raven are describes as either obese or rail-thin, and either way being almost unable to turn down an offer of food.
 * Orks and Trolls in general require much more food than Humans or Elves. There is also a biological augmentation known as the "suprathyroid", which improves physical attributes significantly at the cost of vastly increased caloric intake. This is touched upon more in some of the novels.
 * GURPS
 * The "Increased Consumption" Disadvantage basically means a character will eat much more than their size and weight would imply.
 * Similarly, the "Gluttony" drawback, which can be taken with the "Skinny" drawback. Leading to a character who needs to make a will save not to literally eat any food they see, but (unless you buy off the Skinny drawback) never even hits average weight.
 * Space Marines inside Warhammer 40,000, though they are more ridiculously muscled than thin. Their Super Soldier Bio Augmentation releases hormones in their body for the muscle growth, but such growth still needs to be fueled by their daily feasts (by our standards) and wildlife hunted. They also are able to be Extreme Omnivores, known to eat healthy meals of concrete and metal (and have super-tough bones that only work because their diets are laced with ceramic-based chemicals).
 * The biggest eater of all the Space Marines was the primarch of the Space Wolves Leman Russ. How? He was the only primarch to beat the Emperor in something, twice, namely an eating contest, and a drinking contest.
 * The Tyranids, also from Warhammer 40000, are the pinnacle of big eaters. A race of intergalactic insects who descend on the Milky Way with the intent of devouring all life and natural resources in order to fuel their hyper accelerated evolution process. And if you thought that was enough to qualify for this trope, it is hinted that the Tyranids have already successfully carried out this plan in the past, effectively strip mining several galaxies prior to their arrival here.
 * Some of the books for Werewolf: The Forsaken state that the Uratha have greater appetites than most (partially because they're part-wolf, partially because of the metabolism required for their Healing Factor). As a result, four meals a day is normal for most of them.
 * The Gristlegrinder Ogre from Changeling: The Lost, whose most viable weapon is their teeth. They can be of different sizes but are known for being... well, hungry.
 * Goblins in Pathfinder are specifically mentioned to have unusually fast metabolisms. Pickles are the race's Trademark Favorite Food.
 * Dragon Magazine had a recurring series of humor-oriented short stories called "The Wizards three", supposedly featuring Mordenkainen, Elminster and Dalamar meeting at Ed Greenwood's house to trade spells. All three fit the Trope, often depleting Ed's refrigerator and pantry every time. Eventually, Dalamar was replaced by Mordenkainen's apprentice Rautheene who fit the Trope even more; Ed expressed shock that she could put away entire gallons of butterscotch ice cream without it affecting her slim figure.
 * The Atog creature type in Magic: The Gathering are a race of these. The original ate artifacts, but subsequent Atogs ate things such as enchantments, dead creatures, other Atogs, and time.

Fat Characters

 * Of course, GURPS has the Gluttony disadvantage which can be taken with the Overweight, or Heavily Overweight, disadvantage. And even if the character manages to buy off the Gluttony disadvantage, he won't lose any weight.
 * The Ogres of Warhammer Fantasy Battle have this as their hat, so much so they have twice daily feasts. And they worship a god of gluttony. There is even a point in one of the books where two Ogres eat a five-ton Rhinox in one sitting; by the time they are done they both have more than their entire body mass in raw meat crammed into their stomachs.
 * Ogres from Changeling: The Lost don't have to be fat, but it's hard to be thin when you are literally designed to eat anything on the planet.
 * Sesus "The Slug" Nagezzer from Exalted, whose road to obesity was similar to Henry VIII (see below) -- a war wound left him unable to exercise and work off the massive amounts of food he continued to eat every day.
 * Depending on the edition of Dungeons & Dragons, any wizard who makes a habit of using Mordenkainen's Magnificent Mansion a lot will likely become one. While the interior of the Mansion produces food for anyone inside, it's not real, and whoever eats it becomes very hungry upon exiting, and has to eat a lot to regain his strength. This is only true in earlier editions of the game, though. In later editions the food that the mansion produced couldn't be taken out to be eaten later, but it functioned just like any other food as long as it's eaten inside the mansion before the spell ends.
 * From Greyhawk, the portly wizard Otto (a member of the Circle of Eight and best known for his Otto's irresistible dance spell) was well-known to be a jovial fellow who loved fine food.