STIGMA'S are a largely mysterious byproduct of prolonged vampiric existence. They are certainly more than simple psychological issues, as even the Beast appears to be subject to their absolute nature. And certainly, no amount of psychological delusion should cause one's reflection to disappear. It is clear, however, that stigmas do exist, and can have a profound effect on a vampire's relations to the world.
You may choose a stigma every time you gain an additional Beast-Trait or Inhumanity Trait, but wish to pick the Trait yourself. If you don't your Clan Architect will pick the Trait for you (… and they are prone to pick a nasty one).
You can find more information on the workings of stigmas here.
List of Available Stigmas
AURA OF EVIL: Priests, imams, and devout mortals know instinctively that there is something horribly wrong, even unholy, about you, and react accordingly.
BLOOD BREATH: Your breath smells of dried blood and death, and cannot be covered up.
EERIE PRESENCE: Mortals are instinctively uneasy around you as your predatorial nature activates their instinctive flight or fight response. You are at -1 in all social interactions with mortals.
INFLAMMABLE: Your dead body is particularly susceptible to burning, and once lit by any size flame will burst into a raging fire that inflicts 2 aggravated points of damage per round, causing near-unavoidable fear frenzy (you give away advantage and cannot gain it back, though the +3/willpower still applies), until extinguished.
LUNACY: On nights of the full moon you lose control of your Beast. You automatically rage frenzy on these nights. All night.
NO REFLECTION: You cast no visible reflection in mirrors, water, or shiny surfaces, though you will still be picked up by photography and video even if those devices use a mirror.
PALLOR: You resemble a corpse much more than is usual in a vampire, including visible veins and a sickly pallor. All skill at Masquerade is lost, and purchasing skill in Masquerade is double cost.
PERMISSION: You must acquire permission from someone before entering their home for the first time unless you are invited in by another resident.
REPELLED BY CROSSES: You cannot stand the sight of a cross or similar holy symbol and must spend a willpower point merely to remain in the presence of one. Approach or attack is out of the question.
REPELLED BY GARLIC: You are repelled by garlic and cannot approach it. The presence of Garlic will force you to spend a willpower point or flee its presence. It does not harm you, however.
RUNNING WATER: You cannot cross running water, such as rivers, streams, or running storm drains without expending a willpower point. You can step over a curb that has water running along it, but it makes you uneasy.
SELECTIVE FEEDER: Your feeding is restricted to one particular type of prey. For whatever reason, you believe you cannot tolerate vitae of other types, and you will become very ill if you consume blood of an origin you cannot determine to be within your prey-class. Your prey-class must be described in your SELECTIVE FEEDER jnote, and it must be sufficiently restrictive to exclude at least 60% of possible prey.
TORPOROUS SLEEP: You cannot awake during the day under any circumstances.
ULTRAVIOLET: You are sensitive not only to sunlight, but to intense ultraviolet radiation such as sunlamps. Treat strong UV light as sunlight for all purposes.
UNHOLINESS: You may not tread on Holy Ground, including churches and cemeteries.
VICIOUS PREDATOR: Mortals do not feel ecstasy at your bite, and will react as if bitten by a wild animal, including fighting back. This makes hunting much more difficult.
VULNERABILITY TO SILVER: Damage inflicted upon you by silver weapons is aggravated, and the touch of silver causes you pain.
NATURE BANE: Plants wither, become sickly, and perhaps die when you touch them. Animals find your presence disturbing, avoiding you or attacking you in a greater than usual manner for a vampire. This will make it more difficult to use the ANIMAL hunting method.
COLD: Your touch is just above freezing on direct contact. Air within a foot of your presence is noticeably cold. Moisture condenses on glass. Mortals' exhaled breath is visible. In many situations this will make the Masquerade difficult without dramatic precautions.
SHADOWLESS: You cast no shadow, no matter how bright a light you stand in front of.
PERMANENT FANGS: You have lost the ability to retract your fangs. When you smile, your vampiric nature is plain for everyone to see.
SATANIC EYES: Your eyes have become like those of a serpent or cat. Yellow and slitted, they shine faintly in the darkness, and are quite obviously not the result of contact lenses. This does not give you any vision beyond normal, but may prove a disadvantage in stealth, and certainly will be a problem for the Masquerade.
CARNIVORE: Blood is not enough for your nourishment. When you hunt, you must also consume the flesh of your victims. The Don Juan method is forever barred to you, unless you find yourself a truly degenerate herd. And even then, how long will they last? Note that this does not allow the ingestion of any other sort of food, even flesh that is consumed outside the act of the hunt.
MILLET: You are unable to pass a bowl, pot, or similar open-top container of rice or other uncooked grain without stopping to count each individual grain. Tearing yourself away from this task and turning back requires the expenditure of a willpower point, but you will be unable to pass the container until you have completed counting.