Urgh, this was literally the worst day ever if she can recall. In fact, she recalls it perfectly. She was talking to another female Reaper, a little amusing talk. It was nothing terrible. In fact, the talk was really amusing and fun for her, something refreshing. Yet even then, karma just had to get her.
They were discussing the behavior of one of the Reapers-Sho Minamimoto aka Math Fetishist. What could have been so bad that it reflected karma? Simple-She just had to make a simple joke.
"I bet if I revealed that I was the reincarnation of math he would instantly claim me as his."
Little did she know that this so called "Math fetishist" passed by and heard that exact line. The things which happened next… She refuses to remember nor to reveal. The last thing of that day she remembers was that Sho had his megaphone out and announced that he found the personification of math and that from now on she would be his and his alone. After that everything around her went black and she realized nothing anymore that day. But all she knew for sure was that she was in a big mess now.

"Hey, wake up! Hey!" someone seemed to yell right at her when she regained consciousness. All she knew was that a male seemed to talk to her. Urgh, a male in her room!? Didn't that sign say "KEEP OUT YOU STUPID PIGS!" or was the male incapable of reading!? Time for a scolding!
She opened her eyes slowly, sitting up. She was ready to yell, ready to slap the pig in the face… Yet when she saw a wall she knew that she was not in her room. It was… A different room. All she saw were mathematical problems scribbled on the wall and solved. Geometrical figures drawn and even a sketch of a giant trash pile. What kind of room was this? And whose- Wait a moment!
"Seems like someone finally woke up from their two week long slumber party" the male voice continued. The raven haired female turned to the voice… And then gulped. It… It was him. Him out of all pigs! The math fetishist himself! So that was not a dream she had- "Wait, two weeks?"
"Yeah, two weeks. Exactly 14 days. I'm impressed."
"And you touched me!?"
"No thanks?"
"Why should I thank a pig like you!?" she yelled angrily. What was this guy thinking who he is!? She already concluded this was no dream… Or was it? But then why-
"Something wrong my sweet Math?" Sho then asked, grinning at her which made her disgusted on the inside. 'My sweet', as if.
"Don't refer to me as sweet pig!" she yelled furiously. "And my name is Atsu, not Math!" "Says the one who confirmed that she is the personification of math" he countered.
"I did what? It was a joke you dimwit!"
He chuckled. "Heh, maybe it was. Yet even then I see no reason to let you go anytime soon."
What? Was he serious? What could he possibly mean by-
"Took the time to gather info. A fellow mathematical genius and female at that. Possible personification of math, no casual hectopascal. Zetta sexy if you ask me!" the math freak continued, grinning even brighter. "Why didn't you tell me sooner? We were practically meant to be!"
What? What? WHAT!? "Excuse me!? Are you insane!? I hate men! I hate you!" she screamed at him. "Besides, I remember you hating me too!"
Atsu wasn't far from the truth there. Every time she encountered Sho both were found yelling at each other as if they had nothing better to do for ten minutes. Sometimes he even took out his megaphone to let everyone know that Atsu is 'A meaningless Hectopascal whose existence should be multiplied with a big zero'. She only countered that 'The math loving Pig should just die in a fire and erase his own existence', always across those lines. So hearing him say 'They were meant to be' was the last thing. Even if he was the last other person in the universe she would rather kill herself than repopulate earth with that man. And so she thought he felt about her. But this… This was the exact opposite.
"People change" Sho only added to that. "A lot can happen in two weeks." "Bullshit" she only said, not sounding impressed. "Is this a prank you pigs planned out? Ha ha, funny. Let me go now. Oh you will let me go? Thanks." As she jumped up, heading towards the door yet the male Reaper grabbed her instantly and threw her back to the place on the bed.
"There's no need to subtract yourself from this place yet" he said while holding her down. "I want to get to know you better. I'm 100% serious."
"Get… To know me better?" she asked, yet her voice was still having its disgusted tone to it.
"Oh yes. And that's why I decided that you will stay here."
"Excuse me what!? I sure won't-"
"I already got the permission."
"What?"
"You heard me right" he answered with a big grin on his face, as if he had already won. "Let's have fun together from now on, got it!?"
That… Can't be? Can it? Can it!? Was this the start of Atsu's biggest nightmare!?
However, no matter how many times she closed and opened her eyes, she was still in his room, his face right in front of her. There she realized… This was a nightmare. A nightmare she had started. A nightmare she cannot escape from. A nightmare for eternity.