Age : Mid 40's

Profession : Last resort psychiatrist

Background :

[...]He still retained his consciousness. Hasty prismatic flashes of light scampered through his confused brain and a harsh cacophony of voices almost made him become demented. After a few minutes of embroiling chaos, DKay dissipated himself to the empty void of nothingness.

A maidenly voice woke him up from his slumber. “Stand still. The quicker I can sew you back together, the better. No time to explain.”
As he was lying on what looked like a rudimentary operation table; arms and feet restrained. He tried to say something, but was unable to utter any comprehensible words. Worse, his body was hidden behind a heavily bloodstained cloth. He panicked and tensed every muscle of his body in an effort to free himself.
And as her words reverberated through his mind, the ground below him began to melt and bubble. A dark oozing liquid with the stench of death and decay, pulling him underground no matter how much he struggled.
It didn't make any sense. Was he dreaming ?

He woke up in Hathian lying on the ground. Sweat dripping from his forehead, a cane in his clutched fist, and a searing pain in his right leg.

DKay's past is nothing but a maelstrom of confused memories, overlapping into each other.

When asked about his previous life, or his leg wound - most certainly tied to it - he eludes the question uncomfortably.
His real name, along with how he arrived in CD, remains unknown. However, he remembers wanting to go there in order to treat the mentally ill and the emotionally scarred, most likely as a way of making up for his mistakes.

Unfortunately, he's cursed with a severe form of sociopathy. And while it is possible for him to have civilized social interactions with the world around him, the slightest disruption or annoyance might be enough to flip him out, revealing an individual without a single ounce of humanity.

He commonly refers to himself as "nothing but a mirror", an individual with a wide array of socially acceptable masks, whose emotional response is mimicked and scaled with the one of his interlocutor(s).
In other terms, he's either your friendly neighbor or a fucking asshole.
How he really feels is often impossible to tell. His knowledge in psychology made him more apt at disguising himself and hiding in plain sight. He might give out hints of his condition to his most trusted friends, but it won't go farther than that.

Depending upon his patient, he may give a diagnosis expeditiously and not bother with a follow-up.
Only if he deems the case interesting and if the patient is willing to be cured, will he invest in psychoanalysis/psychotherapy.
(Hello, psychopathic killer #15624. Your illness is incurable, stop bothering me.)

Rest of the story will be made on the spot.