Celia MacLeod, daughter of Crowley, is a 300 year old demon. She was born in Edinburgh, Scotland. In her mortal life, her father cherished her and treated her like the princess she was. However, her father’s early death caused her to go slowly insane. She would sit in the room of the foster home (she never knew her real mom) and remember the good times she and her father had. The memories only made her more upset at the fact that her father’s life was taken too soon. She vowed to get revenge. Even when she killed the one who murdered her father, it wasn’t enough to burn the flame inside her now cold heart. In the winter of 1733, Celia died tragically when a man jumped her and shot her with a rifle. She now joined her father in the afterlife.

When she died, her soul was turned into a demon due to all the past actions she did when she was human. The same happened to her father, who became the King of Hell after Lucifer went crazy and was locked in a cage. Crowley wasn’t the best when he was alive either. Ever since he came out of the womb, his mother abused and neglected him. She eventually left him when he was only twelve years old. He wanted to give to his daughter what his mother didn’t give him. Angered by his death, he killed a few angels in heaven, sending him to the pit. The rugged Scottish man was delighted when his daughter joined him. However, he was enraged when she informed him on how she died.
Flash forward 300 years, to the year 2017. Over the years, Celia worked as a crossroad demon, making deals with mortals who are willing to give up their lives in 10 years in exchange for anything they want. Celia always thought of humans as weak and useless. She enjoyed watching them suffer, as she had no feelings of remorse due to her demon nature. Her favorite part was collecting her part of the deal, sending hellhounds out to rip the humans she conversed with to shreds. She was familiar with every supernatural creature and was acquaintances with most of them, except one species; Angels. Every time she heard that word, she felt the bile in her stomach churn, making her want to vomit. However, she knows them all, so whenever she comes across one, she keeps her cool.
Hunters were probably her biggest enemies. Sam and Dean Winchester were her target for a long time. Pushing their hatred for them aside, she and her father had both worked with them in the past to take down mutual enemies. She even helped Dean get rid of the Mark of Cain, which was a pain to remove. Literally. However what happened next in her new life after death, shocked her and her father to no means end.
In the fall of 2018, she was ordered to go to an auction for the well known Angel Tablet. Her father was attending to some business, so he asked her to go alone. She was fine with it because she wanted to show her father that she could do things on her own. When she teleported into the building that the auction was held at, she saw the Winchester brothers. Kevin Tran, the Lord’s Prophet, accompanied them. They were talking to a guy wearing a red and white Wiener Hut uniform. Immediately, she knew he was an angel. The youngest one, to be exact. When, she walked over to them, she put on her best smirk.
“Hello, boys.” she said her father’s catchphrase in her thick Scottish accent.
“What are you doing here?” Dean spat at her while Sam just glared.
“Getting the Tablet. Are you that thick, Squirrel?” she smirked then turned to the slightly scared angel. “Samandriel, long time no see.”
“Get out of here, Celia.” Samandriel warned her, but he didn’t sound intimidating. The only angel that actually sounds intimidating is Castiel; heaven’s most wanted Angel. The angel never scared her, though. She learned to be feared not to be fearful.
“And why should I do that? Miss out on all the fun?” Celia replied in an alluring tone.
She started walking closer to Samandriel to scare him. She has to admit, his current vessel called Alfie is pretty cute. She ignored it because whenever she thought a guy was cute, she would have her way with him. Her father doesn’t want her to have any relations with angel. Samandriel started backing away and lucky for him, Dean stepped in.
“Celia, stop. Don’t hurt the kid angel.” Dean stood between the demon and the angel.
“Who said I was going to hurt him? I was just trying to scare him. However, I could hurt him if I want to.”
“You wouldn’t. You may be a demon, but you wouldn’t hurt an angel.” Sam intervened.
“Watch me, Moose.” Celia looked over at the poor angel and he started choking and felt his stomach being squeezed. Samandriel collapsed onto the ground and started screaming for her to stop. She shockingly felt a bit of remorse for him, which caused her to stop.
She will never admit to it, but she didn’t want to hurt him, but her pride and arrogance caused her to do it. She refuses to be referred to being weak and she didn’t want to disappoint her father who was the only person she cares about. Celia has no idea why she felt bad for hurting innocent Samandriel. She normally takes pleasure in hurting and torturing. She thought for a moment, Am I still slightly human? Have I gone soft? Why is this happening? Am I falling for him? She shook the thoughts out of her head. She’s losing her game. She came here for one thing and one thing only. The tablet. Every demon and angel know that Celia will do anything she needs to get what she wants.
She thought about killing Sam and Dean, but her father wouldn’t allow it for some unknown reason. They have killed many of her friends: Abbadon, Lilith, Ruby, Alastair, the list goes on. She loathes the brothers, yet she gets excited whenever she sees them. Maybe it’s the thrill of getting to annoy them? Celia, plus the others, were guided into a room filled with chairs. People staring bidding for the randomest things, things that Celia could retrieve easily, being a demon and all. Then, came the biggest prize, the Tablet.
“Who would like to start the bidding?” the demon running the auction asked.
“Three billion dollars!” Celia yelled. Her father has a ton of money, she could bid as much as she wanted.
Suddenly, Samandriel stood up. “The Mona Lisa.”
“Four billion dollars!” Celia added to her bid. She smirked at the angel. She always loves a good competition, as long as she wins.
“Vatican City!” Samandriel shouted. He seems desperate to win. Make sense, the Tablet belongs in heaven.
“The moon!” Celia was running out of ideas. She needed to go big in order to win that tablet.
“You’re bidding the moon?” Dean turned around and said to her.  
Celia recalled a time when she made a deal with a young man who wanted to be the first person to step foot on the moon. A smirk appeared on her face when she remembered when he meets his fate. Good times. The auction for the Tablet went on for a few hours when it was sold to Kevin’s idiotic mother who sold her soul for it. Embarrassed by her failure, Celia left the auction and went back to her father’s hideout. Once she got there, she saw her father smirking and holding the tablet. Her eyes widened in shock.
“How did you-”
“I have my ways.” Crowley said, leading her to the chamber where he keeps his prisoners.
Celia could hear screaming and pleads to be released before her father even opened the door to the cell blocks. She followed him down the corridor until they came to the last cell. To her surprise, Castiel sat in the cell, covered in cuts and dried blood.
“Before Ms. Tran could give up her soul, Cas here swiped it. I followed him then decided to kidnap him. I tortured him until he gave up the tablet.” Crowley explained to his daughter. He always loved teaching her his ways.
“Dad, you’re awesome.” Celia said as he gave her the angel blade, the only thing that can injure and kill angels.
“I know. Now, Cas disobeyed Heaven and will suffer severe consequences once the angels find him. Since he did something nice for us, I think we should do something nice for him. End his pathetic self before his brethren do. Care to do the favor?” Crowley suggested with a smirk. Smirking was something the MacLeod family does a lot. 
“It would be my pleasure.”
Celia opened the cell door, blade in hand. Ignoring Castiel’s pleas to be spared, she drove the blade straight into his heart, killing him instantly. His dead body laid on the cold stone floor, a shadow of his burnt angel wings stained the ground, reminding of who he was. Since she was a demon, Celia felt no remorse, only pride, in killing Heaven’s most wanted.