Contrary to some paranoid religious groups, Dungeons and Dragons is not Introductory Satanism 101; and contrary to popular culture depictions, gamers aren't all a bunch of maladjusted nerds. I do agree with this article's analysis of the show Big Bang Theory, for example, pointing out how popular culture completely misses the mark in depicting all things geek.
With that said, there are still some stereotypical gamers who should be avoided at all costs. Sometimes the Game Master (GM) has ways to deal with these players, but not always.
The Nurgling
Some people are utterly fastidious about their personal hygiene. Some are less so, but still attempt to maintain a decent level of cleanliness in public. Then there's our subject...
The Nurgling is almost always obese, and invariably has a bad case of plumber's crack exposed if you have the misfortune to see the back of his folding chair, because he wears ill-fitting blue jeans and a tattered and stained t-shirt of insufficient length. The guy also apparently has a phobia about showers, and if you're lucky, believes enough Old Spice will eventually mask his stench. If you're not lucky, Army Surplus gas masks will not protect you.
If you are the GM or owner of the game venue, warn once at most, and then banish.
The Loudmouth
I don't just mean someone who forgets the concept of "Inside Voice" from time to time. I mean the socially-maladjusted individual who cannot allow others to have their moment of attention even when it's their turn to play. This person speaks loudly all the time about everything but the game being played at the table.
Unlike the Nurgling, there are ways to deal with the Loudmouth within the game. For example, I once had an encounter with this kind of person at a Dungeons and Dragons 4th Edition game at the local game shop.
It was the officially-sponsored weekly game night supported by publisher Wizards of the Coast, so anyone was welcome to join. However, this person rambled at great length and high volume about movies, TV shows, internet memes, and anything else that popped into his head. Repeated polite suggestions to be more courteous were made by the GM, but this loudmouth would heed none of them.
One of the other players became quite frustrated, and finally decided to act. When Loudmouth's character fell from a cliff edge and was hanging onto a small ledge 20 feet below the surface due to his lack of attention to the game, this other player asked the GM if his mage could create an illusion of a bridge beneath Loudmouth since his skills included illusion magic. The GM asked the mage player to roll a die in order to see whether he was successful. He was.
The GM then turned to Loudmouth and said, "You see an old stone bridge about 10 feet beneath you. What do you do?"
Loudmouth stopped his irrelevant yammering at me to say, "I let go and drop to the bridge!"
The GM replied, "You fall another..." rolls dice "...30 feet and take damage."
The best part: This happened twice in a row! Loudmouth got mad. The GM explained what had happened, and that Loudmouth had brought this on himself by antagonizing the other players and refusing to be a good participant in the game. Loudmouth left, never to return, and subsequent weeks were much more pleasant for everyone.
The Munchkin
Munchkin is a hilariously fun card game. It satirizes a certain type of tabletop RPG player who exploits, bends, and sometimes flagrantly breaks the rules of the game in order to win at a game where cooperation is the focus rather than personal glory and optimal mathematical probabilities.
Remember, whether playing the venerable Dungeons and Dragons or the saccharine-sweet Tails of Equestria, the game is fundamentally a cooperative storytelling venture where the GM creates the core structure, and the players play the role of a character in the story. The Munchkin sucks the fun out of the game, and doesn't play a role so much as he tries to take center stage and overshadow literally everything that happens.
Like the Loudmouth, the Munchkin can be wrangled back into line by a good GM, and can potentially be redeemed as a well-mannered gamer.
The Pervert
There is no redemption here. The Pervert is usually a guy who wants to play a stripperiffic female character and wants to turn every encounter into an orgy. It usually keeps its game info in a binder bedecked with a bikini-clad anime chick, so it is easy to identify before the game even starts, but sometimes they manage a modicum of subtlety against all odds, so always be on the alert.
This thing kills games more than the Munchkin and the Loudmouth, and is more disgusting than the Nurgling. Avoid at all costs. If it's a player, kick it out. If it's the GM, find another GM. There are no other solutions.
That Guy
If you ever meet someone who fills all of the categories above, run away and do not look back. Trust me, it's the only option to retain your sanity, and Miskatonic University researchers don't even want to explore that level of mind-melting horror.
