Casper's back story in brief is that he was once a human boy. After death, he turned into a ghost. However, he is different from other ghosts as he is friendly towards humans.
Briefly, Casper was a young human who passed away. Now as a ghost, he has a reputation for being friendly. His back story is centered around his transition from a human to a friendly spirit, and his attempts to interact with the living in a positive way.
Well, Casper's back story is quite interesting. In some versions, he was a young boy who died unfortunately. His family might have been through some sort of tragedy too. As a ghost, he retained his childlike innocence. He found that scaring people wasn't his thing and instead chose to make friends with the living. His back story also includes his interactions with other ghosts, some of whom are not as friendly as he is.
Hodor was originally Wylis. When Bran was in a dangerous situation, he warged into Hodor's mind. This event somehow damaged Hodor's mind and left him only able to say 'Hodor'. It was a tragic event that changed Hodor's life completely.
Ultron was made by Stark and Banner but turned bad and wanted to destroy humanity.
Kuromi is a Sanrio creation with a back story of being different. She's a bit of a troublemaker, and her story is centered around her non - conformist attitude compared to other Sanrio characters, especially in relation to My Melody.
Sure. Catwoman, Selina Kyle, often had a tough upbringing in Gotham. This led her to a life of stealing.
Sure. Selina Kyle is Catwoman. She grew up in hardship and turned to thieving. She's known for her cat - like skills and has a complex relationship with Batman.
Sure. Kirishima wanted to be manly. He used to have doubts about himself but was inspired by heroic figures. He trained hard to get stronger.
Snoke was a major figure in the First Order. He had an interest in Kylo Ren and trained him. His own back story wasn't fully detailed, but he was a significant threat in the Star Wars story.
The Terrifier is a horror icon. His back story has elements of him being a deranged and violent being. Not much is clear about his origin but he is known for his extreme acts of brutality.
Trump comes from a wealthy real - estate family. He got his education and used that knowledge to expand his family's business. Eventually, his fame from business led him to consider a political career.