A caged bird will only sing if it has never known freedom.
He comes across as brattish and sulky, though it is mostly a passive-agressive reaction to his lot in life. Being a complete pain in the ass is one of his few joys in life. When on the job, even this shallow facade fades behind a porceline wall of dispassionate obediance.
Valentine is not permitted any personal ownership over his tools and equiptment, but he utilizes several focus tools of ritualistic nature which aid and lessen the strain of, though are not absolutely essential to the use of his Talent. These tools include, but are not limited to mirrors, insense, and personal artifacts formerly owned by the spectors he summons from the netherworld.
Valentine was born within a brothel to a common prostitute. Rather than being born in Februrary, he was instead named in favor of the holiday, on which his mother was told, as a gift, that she would get to 'keep this one' as a gift of rest. Whatever favor his mother might have been shown during that time period faded soon after his birth, likely due to the fact that she gave birth to a boy instead of a potentially valuable girl. To placate her pimp, his mother often dressed him as a girl in his infancy and early childhood, though this did not save him from general abuse and neglect.
His mother's disfavor increased over time, comming to a head when Valentine was seven, when his mother's pimp murdered her in a fit of rage. Soon after, Valentine's abuse turned sexual. It was enough to snap free his Talent's potential. Accidently summoning his mother's ghost, she proceeded to haunt her pimp until he succumed to madness and drowned himself on a lethal cocktail combination of opiate drugs and alcohol. The power vacuume caused a particular brand of chaos that resulted in Valentine comming to the attention of Doctor Erus.
While the transfer from brothel to research center lessened certain brands of abuse, it offered others in exchange as his Talent was explored, probed, and trained to profficiantly explored levels. Valentine was clinicly molded into a conveniant and descrete assassain, trained to send spectors to chosen targets, to be killed at a distance in much the same way that his Talent caused the death of his mother's pimp. Ten years after his 'adoption', little remains of the child he never truely was, and his is, perhaps, much too far gone in his misanthropy to be recovered.