I'll make the first character! 

Name: Benedict Wigglestein Uno Jr. Goes by "Father". 

Race: Former human, now some sort of demonic silhouette creature.

Age: Physically middle-aged, unknown real age.

Appearance: [url=http://img1.wikia.nocookie.net/__cb20130108221237/knd/images/a/a8/Father.jpg]Link[/url] Father is of average adult male height and weight. He wears a silhouette "suit" that gives the appearance of black skin, yellow eyes, and a red "outline". Underneath that he wears square eyeglasses, suspenders, black pants, a white button-up shirt, and dress shoes. He never takes off his silhouette suit. Father is always smoking his pipe, which is also silhouetted. 

Personality: Father is downright evil. He hates children to the point of "ageism". (like racism, but for age.) The KND consider him their worst enemy, even though he rarely fights himself, instead choosing to send his "adopted children"--the kidnapped and brainwashed Delightful Children From Down the Lane--to do all the work. He is very impatient, irritable, and sarcastic, as seen from many talks with the DCFDTL. When angered he burst into flames and his offensive powers seem to increase. 
When he's happy he can be humorous, but this is rare, since he is almost never happy. 

Alignment: Evil, specifically on the adults side of the war of adults against children.

Universe: Codename: Kids Next Door.

Powers: Father is most known for being able to burst into flame and shoot fireballs. He can also levitate (usually used instead of walking) and use telekinesis. 

Magic: None, he's already pretty powerful. 

Specialties: Fire-based attacks.

Special weapons?: In his universe Father is capable of making some pretty powerful technology, but he won't be using any of that here. 

Strengths: Very powerful, especially when angry. 

Weaknesses: Water and cold objects, such as ice cream. It extinguishes him and renders him powerless. 

Bio: Father is the son of Benedict Wigglestein Sr--also known as "Grandfather"--who is another evil demonic being with anger managment issues. Grandfather abused his two sons--Father and Monty Uno, who would become the 7th founder of the Kids Next Door--and Father soon become totally obedient in all ways and thoughts. He inherited Grandfather's hatred of children and the position as the sole oppressor of children. At some point he moved from Britan to the Unites States, created the Delightfulization Chamber--which branwashed Sector Z of the KND and turned them into the Delightful Children From Down the Lane--either bought or built his mansion--the Delightful Mansion From Down the Lane--and started fighting the Kids Next Door. He gathered more minions, such as the Ice Cream Men and local teenagers. He frequently works with the other evil adults, like Mr. Boss.