Karl Kyle

The second child of Gotham harlot Maria Kyle, Karl Kyle was blamed by his mother for the drastic change in her body that was the result of his birth and the resultant loss of her upper class clientele. In addition to the already painful upbringing he would have as the child of an East End prostitute, Maria frequently abused and/or neglected him.
Eventually being picked up by child protective services, Karl would soon be lost and the system and end up first living with a mad cat-woman before becoming a labor-boy in a Chinese restaurant that illegally supplemented meat with cat.
After aging out of youth services Kyle immediately ended up on the street, though he was not alone, for he always had a cadre of cats with him, as if he spike their language. When news broke of the Catwoman in Gotham, Karl viewed her as his conquest-destiny; given a life defined by cats he was the Cat-King and she would be his Cat-Queen. Thus, he made a costume similar to hers and began his pursuit. Committing Cat-themed crimes to win his Cat-Queen's affection, he would not only cross her path but that of her true amour, The Batman. He was driven to fits of rage by her dejection and her affection for Batman, and his behavior became increasingly unhinged. When he found out that Catwoman was his younger sister Selina he was so far gone that this did not deter him. 
== Early Life ==
Before Karl was born, his mother Maria was perhaps the top prostitute across all of Gotham, having regular clients in the mayor and police commissioner, but especially leading mafioso Carmine Falcone. Carmine had what one might even consider an affair with Maria, which ended the day she began showing her pregnancy with her second child, Karl.
After giving birth to Kyle, Maria's body was too drastically altered and she lost her top-level client base. From then on, she and Karl, and his older sister, Maggie, would live in the East End, one of Gotham's most historically impoverished and crime-ridden areas.
Blaming Karl for the loss of her career, she abused him from a young age. Typically she hit him until his skin was purple from welts, but in some instances she'd lock him in a closet for a day at a time. This was all on top of the frequent neglect the children already experienced, often going without food or attention food for long stretches of time and not having adequate clothing and living conditions. 
But at one point his mother's abuse reached a high. One night Maria was being visited by a john, as typical. When he saw that she had a young son, he offered her double her pay to rape him instead, which she accepted. Fortunately, the man would later be killed in a shoot-out and this would not endure.
Karl's only salvation was a stuffed cat he shared with his younger sister, Selina.
When Kyle was nine, Child Protective Services investigated Maria (On a tip from a John she had shorted) and the children were taken from Maria. They were separated, and Selina was allowed to keep the stuffed cat over Karl.
== Origin ==
The first foster to take Karl in was a kindly young woman. Hopes for a bright future were deflated when Karl was put in the care of the woman's mother, as she had fostered him to give her mother something to occupy herself. She was a manic elderly woman who cared for several dozen cats, more so than for any human. Karl was put to work by the woman performing nonsensical tasks to entertain her delusions. Subsisting on nothing else herself, the old woman fed Karl cat food, often expired, before she was eventually declared unfit. He would next be taken in by a Chinese couple who ran an ethnic restaurant. There he was again put to work, but it was a somewhat better environment. They were strict and unforgiving, and gave him food and a bed to sleep in. It wasn't long into his time with them that the restaurant starting under-performing right on the onset of a health scare in chicken. The owners turned to putting cats in the food instead, making Karl catch them off the street and skin them, in addition to eating them.
When Karl turned eighteen, he was out on the street, and having no skills whatsoever wasn't eligible for any kind of work. But it seemed he had an affinity for cats, particularly alley cats, who would accompany him as he wandered the streets of the East End. His mental health growing worse every day, further so by his constant exposure to cat urine, Karl became delusion and considered himself to be a cat.