Chubby!SebastianXDemon!Reader- Mates

It was an ordinary day at the Phantomhive manor;Ciel yelling at Sebastian when Grell decides to pay a visit to the manor. Ciel and Grell,both knowing what Sebastian has done to them, were plotting a little "sweet" revenge for him.

They had made a cake for Sebastian, but not just a normal cake. This cake had a special chemical in it that would make Sebastain pack on the pounds like crazy.

They brought him in thanks to Ciel ordering him to follow along and they sat him in a chair and began to give him the cake.

He ate it, slightly suspicious, but hungry none the less. By the time the first slice was into him, Grell and Ciel started cackling.

"What's so funny?!" He demanded.

"Just wait till tomorrow!" Grell said, taking off.

Ciel smirked and left him quietly leaving a supicious Sebastian to find out his new surprise.

Sebastian soon felt drowsiness overtake him once he reached his bed chambers. He passed out, belly up in his bed.

About 9 hours later, Sebastian woke up....a lot bigger than when he went to bed.

Sebastian gasped slightly as he looked in the full framed mirror, letting out a sigh as he got dressed and went to wake the young master for his regular schedule.

Ciel had set out a new set of clothes for Sebastian; for his old ones wouldn't even come close to fitting. He was now at least a good 375 pounds.

He waddled down the stairs and saw Ciel laughing at him.

"You're an ass...." Was Sebastian's only response.

After he finished his laughing fit, Ciel handed him a list of errands to run. One included running to Downtown London.

When Sebastian had finished his errands, including the running to downtown London, he was very winded and sweaty which caused him to send out a horriblely foul scent since from being such a heavily sized demon.

A young girl of about Sebastian's age saw the obese demon, leaning against a building and panting, carrying some bags.

She sensed that he was a demon because of the scent he omitted. Why could she? She was a demon herself. Her black hair fell down to her waist and her eyes were as red as Sebastian's. She wore a short sleeved black and white dress.

Sebastian had caught her eye. Not only was he another demon, but a fat one at that. She loved her mate's to be big and round and fat; a rarity for a demon. She had only had one mate like this before and it was centuries ago and they didn't even mark each other; it was just a one night fling. It didn't work out, but she saw massive potential in Sebastian.

"Wow." She said, approaching him. "What's a good looking Demon boy doing around in London?" She asked, teasing him. Sebastian felt her demonic presence and smiled. It had been ages since he found a potential mate.

" I wouldn`t call my self good looking anymore." He said as he looked down at his form " If you must know I`m just running errands for my master and if I might say you`re a lovely demoness. What brought you here anyway?"

She immediately recognized him. "So you're the famous PhantomHive butler? What is it? Sebastian Michaels? And if you must know, I'm (name). My former Master recently gave me his end of the bargain and now I have free reign for a while." She said, presenting him her delicate, black polished hands.

He nodded " I see you too have heard of me. As you can see, I still have a master and he decided to get revenge on me by doing this." He plainly said, patting his big belly, annoyed by his body as he eyed the beautiful demoness.

She approached closer. "Tell him that he did a good job..." She said, batting her ruby eyes. Sebastian smelled the scent of lust flying off of her....and of himself. She was a beautiful demoness and would be an excellent mate for life. Besides popular beliefs, demons preferred to mate for life....or I guess afterlife.

He chuckled. "And what? I suppose you're one of those, what the humans call, chubby chasers aren't you?" He said, straightening himself out.

(name) giggled " You could say that, but that's not the only thing I`m after" She ran a pale hand down his body.
" Oh and what`s that?" Sebastian asked as he shivered from her touch. " I`ve been looking for a mate and you seem like the perfect one. What do you say? would you like to be mine?" She looked up at him with big ruby eyes, causing Sebastian to fall even more in love with her than before. " Of course I would. After all, I haven`t had a good mate in a long time and it does get rather lonely I admit."

Their pheromones changed to those of compassion and love, and still some of lust. They walked hand in hand down the streets.

"Little Master won't mind if you stay with me. If he does, I'll break the contract myself." He said, winking at her.

She giggled and followed him into the house. Back inside, Grell and Ciel were making fun of the obese demon, completely clueless of his new courtship.

Grell was the first to notice the demoness " Bassy, who is that?" He looked at (name) with complete jealousy. Sebastian chuckled " (name) is my mate." Ciel burst out laughing " Your mate?!" He sneered " What women or demoness would have the slightest intrest in a fat ass demon butler like you?"


An animalistic urge overcame (name) as she pinned Ciel up against the wall by his throat.

"I would happen to be the one who is mated with this supposed 'fat ass'. Now, you will keep your mouth shut about my mate and I. I will be staying here until you fullfill the end of your contract." She released the terrified Ciel afterwards. Sebastian hadn't  seen a demon woman so hostile in ages and he hadn't been this turned on in his entire life.

" Y-you are free to live here and do what ever you want?" Ciel said for the first time ever really terrified. Sebastian smirked " Come I`ll show you to your room." He took (name) by the hand gently and led her up the stairs.

"These are my, I mean our, chambers." He said, showing her their red and black bedroom. She jumped on the bed, motioning for him to sit with her. He flopped his fat body on to the bed with a great creak.

She cuddled close to him. Demons would never marry, but would make contracts with each other, marking each other to be betrothed in their own way.

Sebastian pulled her close kissing her passionatly as he ran his hands through her dark hair and down her slender body

She massaged his rolls and traced his creases. She stopped him though. "Darling, don't you think we should make a contract?" They both knew that this would last eternity.

They summoned one and marked themselves. Mates' marking were always in a more intimate/ private area. They had chosen their asses. On hers was Sebastian's marking and on his was hers. Both appeared to look like tattoos. Of course, they were already naked at this point.

Grell was super jealous now and was watching through the key hole and Ciel was listening.

"Now? Where should we start?"

He smirked " you pick."

Time skip: a couple months later.

Sebastian was downstairs getting tea for not only his master, but also for his mate. She was with child now and a pregnant demoness was one of the most evil creatures you could find. Unless it was their mate, they would rip a person's head off for even saying hello. Ciel had Sebastian take care of her. He wasn't getting choked again.

Sebastian brought the drink to his mate who was sitting on their bed under the covers.

"Good morning, darling." He said, sweetly.

(name) smiled up at him " Good morning." she replied softly. " I made you some tea to relax you" Sebastian said setting the cup down on the table beside the bed and sat beside her. She picked up the cup and drank some of the tea and set the cup down. " How is it?" Sebastian asked. " It`s perfect." (name) said with a smile.

Time skip about two years:
(name) had given birth to a set of twins; one boy and one girl, named ( names of choice). Sebastian sat holding the girl as (name) was holding the boy happily as Ciel was watching the two with their children. " I couldn`t have asked for a better mate than you (name)" Sebastian said, kissing her. She smiled back at her chubby mate. All was well.