Hm. Masks. The primary true mask Aria wears is one of calm, intellectual civility, even when dealing with people and ideas she holds in scathing contempt. This tends not to crack even in private unless Aria does not feel like she has to be "careful." She has the most trouble maintaining it around bullies, people who undercut their own causes through ruthless stupidity, and free-willed minions of Sansha's Nation.
An alternative "mask" occasionally comes out when the first cracks. This is Aria at her most passionate, trading in calculating calm for potent, blunt sincerity, often in the form of eloquent rage. Aria herself is not certain whether this is a genuine display or not-- she often surprises herself with the intensity of her own emotions, which makes her wonder whether they're real or just an act that is not apparent even to the actor.
Otherwise, she mostly doesn't wear masks so much as "facets"-- she's pretty continuously the "real her," but seen from different angles. Any given exchange with Aria is like shining a light through a concealed, prism-like object and seeing how it refracts. Unfortunately, even she is not aware of all her own angles, so the results can be unpredictable. Any good intentions she might have often run afoul of a perverse streak an AU wide.
* Though a moral relativist, she tends to describe herself (and other infomorphs) in terms that imply moral condemnation, as monsters or demons. She's deeply spiritual, yet freely admits that she has wandered so far from the well-trod paths of wisdom her sect describes that she may never find her proper place again.
* She's a cold-blooded killer on a pile of different levels, but has a compassionate heart. Her first impulse on hearing of a problem is usually to try to provide helpful advice.
* She withholds moral judgment, but openly regards most people, including herself, as "fools," and especially despises those who undermine their own causes-- whatever those causes might be. This is one of the easiest places to see cracks in Aria's mask.
* She's risk-averse, and introspective to a fault, yet prone to taking drastic actions on impulse.
* She's both aggressively pedantic and aggressively courteous.
* She takes intellectual honesty extremely seriously, both in herself and others. In fact, she rarely lies at all, preferring to offer perspectives on the truth even when her aim is deception.
* In keeping with the above, she's one of the very few infomorphs in New Eden who will freely and cheerfully admit to being a hypocrite.
* She's fond of mind games and deception, so long as it remains impersonal. Personally, she's a creature of her word and intensely loyal. She's also quick to forgive (though not to forget) personal betrayals.
* While she claims to seek wisdom, she nevertheless clearly has a high opinion of her own insights and a fondness for the sound of her own voice. She describes herself as "clever" rather than wise, but tends to play the wise woman.
* She has a special love for intellectual, religious, and philosophical mazes, which she uses to protect and justify herself. Whether these mazes double as actual wisdom of any sort is left for others to judge: Aria is most often the first to get lost in them.