Magic is power. Magic is dangerous. Magic is fickle. Magic will get you food if you are clever enough to steal it, which Selina certainly was. Or so she had thought until five seconds ago. Who would've though a wizard would set a trap which didn't bother to keep people out but was only sprung when people tried to leave?
Well, the trick is one she'd remember...assuming she managed to escape.
No binding circle beneath her, so she stayed where she was as she looked about to see if she could figure out the spell. Windows? Possible, but the odd glint of light on them suggested something more than glass. The heating vent? The door? The door maybe. Limited options but it seemed either the windows or the door.
Wait, why did she forget the vent?
The door seemed solid. Oak and a complex lock. Could she pick it quickly?
Wait. There was something she kept forgetting......the vent. Damn. Okay, some sort of spell to distract...
The window locks looked spelled shut and she didn't have any counter charms with her. Why didn't she think to bring counter charms? Bad form.
That door lock though. She stepped forward, focusing on the door and pulling an end table to rest beneath the heating vent she was forcing herself to not think about. A figurine on the table shifted and nearly fell but she caught it. A black cat, onyx. Might be worth something so she pocketed it.
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Later, once she was several blocks away and certain there weren't any guardians following her, she sat down on a gargoyle to watch the night sky of Gotham. The city's light always made her feel like she was at home, and the glow of spirits as they went about their master's bidding just added to the picture.
Sighing, she pulled out the figurine and examined it closely. No signs of glyphs or wards, so she was fairly certain its previous owner wouldn't be tracking her that way. It was a pretty thing. Pretty enough, she'd regret having to sell it. It was poorly cleaned however. Horrible really, to have such a nice piece and leave it dirty? Ugg.

She didn't notice the smoke and shadow that began to coalesce as she rubbed at the figurine until a whispering voice said, "You could keep me and I could aid you in procuring food, among other things."
Started, she nearly lost her seat, not to mention dropping the figurine.
"I wouldn't do that," the cat composed of smoke and shadow said with a glance down. "I doubt you would survive the fall and I would then be saddled with a new owner."
"I'm your owner?" Selina asked, quick witted as always. "I don't think I like the idea of that."
"Never the less, you hold the figurine, thus I must obey."
Part of her thrilled at having the power over a spirit, but the better part of her was repelled. Yes, spirits, like magic, meant power, but enslaving another will for your benefit was aberrant to her. "How do I free you?"
"I am afraid that knowledge is not among the many subjects I am aware of."
"Okay, how about this then. I will guard the figurine and we can work together--I mean it, together--until we can learn how to free you."
"You are a strange sorcerer."
"I am not a sorcerer. Never had much education."
"That would explain it. Very well then...how shall I call you?
"Selina. And how should I call you?"
"Cat will do."
"Cat, then. I think we have ourselves the beginning of a wonderful partnership."