I'm gonna do this in first person, since I suck at writing in third :p (I hope it's okay if she and Calcifer can be cousins, as it pertains to the story and they share some similarities in design)
Also I hope it's okay I made it into an interview-story type thingy.
(Warning: Large-ish amount of text)
The InterviewI walked into a small, unfamiliar room. The wallpaper was solid grey and peeling, but the soft charcoal carpet made the room more comforting. The only pieces of furniture were an old cherry wood desk and two patched-up - but comfortable-looking - chairs. I cautiously sat down on the edge of the chair in front of the desk. I chewed the inside of my cheek and stared at the battered clock that hung above the door.
After what seemed like a decade, another foxer
finally entered the room. She was middle-aged, and not very attractive, but who was I to judge?
"You must be the twelve o'clock," she said in a businesslike manner. The foxer sat down at the chair behind the desk, and removed a clipboard from one of the drawers. She took a pen from behind her ear, and clicked it once. I noticed a nameplate on her chest that read, 'Mrs. Greenblatt'.
"So," said Mrs. Greenblatt in a gravely voice, "Can you tell me your full name?"
"Liadan Isienna Rosewood," I replied morosely.
Mrs. Greenblatt glanced at the clipboard, then looked back up at me, sucking on the end of her pen. "Any immediate relatives?" she asked in a monotone.
"N-no," I stuttered, "not unless you count my cousin Calcifer."
"Hmm. I see," said Mrs. Greenblatt, checking the clipboard once more. "Let's get straight to the point, Liadan-"
"It's Lia," I said quickly, cutting her off. I immediately regretted my choice to interrupt; Mrs. Greenblatt was glaring at me from behind her glasses.
"Well then,
Lia," she said slowly, putting emphasis on my name, "let's get straight to the point. Why are you here?"
"I-um-wh-what do you mean? I-I set up an appointment," I replied, shrinking back into my chair.
"I know that," Mrs. Greenblatt snapped, then went on more calmly; "Why did you set up an appointment? Do you believe yourself to be a danger to others? It says here that you have had violent episodes in the past."
I swallowed before answering. "I-yes, no, maybe, I don't know!" my voice had risen while I had been speaking. I took a deep breath, then shrank down even more into my chair and whispered, "Sorry." I took another calming breath before continuing. "It's just that, recently, I've been more depressed, and more liable to snap."
"Increase in depression and violent tendencies..." Mrs. Greenblatt muttered under her breath, jotting down notes on the clipboard. "And what do you do when these two things happen?"
"I usually write poetry, and listen to music," I explained. "Sometimes, I draw or paint."
"When did this increase in destructive behavior begin?"
"A-about five years ago... w-when I first discovered my talent..." I looked at the floor, not meeting her eyes.
"And what is that?"
"B-breaking hearts," I held up my right paw. The glass heart with the large fracture in the side glimmered in the light, casting a rainbow onto the floor. "Or, at least, that's what I think it is."
"How did you get your charm?" Inquired Mrs. Greenblatt. She seemed genuinely interested now.
"I-it's a long story," I stuttered.
"I'm listening."
"Well, it all started with-with my aunt. After my parents died in that car crash, she took me in. She was sweet, n-nice, a-and caring... b-but, she already had a ch-child; my c-cousin, Calc-cifer." I took a breath to steady my voice, the continued. "Well, one day, when I was a young teenager, Calcifer was stealing my things. I tried to get them back from him, but he kept running all over the house. I chased him upstairs, and ran straight into my aunt.
'What's wrong, Lia?' she asked kindly.
'Calcifer took my photo album!' I screamed.
Calcifer's mom looked from me to him. 'He just wants to see what his aunt and uncle looked like,' she said.
'I don't care!' I yelled. 'I want it back, NOW!' I ran around my aunt, trying to get at Calcifer, but she grabbed me by the arm.
'Let him have a look,' she said, 'It won't do any harm.'
'WHY, SO HE CAN SEE THE PEOPLE YOU KILLED!?' I screamed, tears pouring down my face. My aunt blinked in surprise, releasing my arm. '
YOU WERE THE ONE DRIVING THAT NIGHT! YOU WERE THE ONE WHO GOT DRUNK AND CRASHED RIGHT OFF THE ROAD INTO THAT TREE! I REMEMBER EVERYTHING NOW!' My aunt didn't say anything. She tried to put her arm around me, but I threw it off. 'IT WAS ALL YOUR FAULT!' I screamed, pushing her with every word. Calcifer watched in utter horror, my stolen items lying forgotten at his feet. I gave my aunt one last push, and she tumbled down the stairs. I grabbed onto her at the last minute, horrified at what I'd done, but it was too late. Her body broke my fall, and I heard a snap that could only be the breaking of of a neck. I got up, trembling and terrified.
'MOM!' Calcifer yelled. He ran down the stairs, over to his mother's body. 'Sh-she's not b-breathing,' he said shakily, then burst into tears. 'WHAT HAVE YOU DONE?!' he yelled at me. 'Why... mom, come back, I still need you...' Calcifer turned to me, glaring through reddened eyes. 'MURDERER!' he shouted, over and over again. That one word reverberated in my skull as I fled from the scene. And, to answer you're question, th-that's why I'm here," I finished. I was surprised to find that I was in tears, although I shouldn't have been.
"You've just confessed to murder," said Mrs. Greenblatt after a long pause. "You could go to jail for this."
"I wasn't in the right mind," I half-whispered. "I feel like I'll never be happy again. The guilt is gnawing away at my very existence."
"Well, in that case and in light of the evidence shown, I hope we can help you. Welcome to our facility, Mrs. Rosewood."

By me (the blood is figurative, not literal, it symbolizes Lia's guilt)