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Light woke up one morning with a feeling in his gut that was familiar as much as it was torturous. His body ached, and it felt like there were knives in his stomach.
Damn it. Why did it have to come now?
Upon further reflection, he realized that it was the 19th of the month, meaning that he was due to start today. Light’s menstrual cycle had always been incredibly regular. But for some reason, he always forgot when he was due to start until it had already happened. The experience was so awful every time that he managed to block it out of his memory until it came again.
Light took a deep breath. Maybe he’d get lucky this month and it just wouldn’t come. Maybe he just had a stomachache or something. With a shaky hand, he reached down and touched a fingertip to the crotch of his boxers. He held up his finger and saw blood. Fuck.
Just then, a particularly nasty cramp wrenched its way through Light’s body, causing him to moan and curl in on himself. He needed to get out of bed and clean himself up. He needed to take some painkillers. But he couldn’t get up. All he could do was toss and turn and bleed and suffer.
“Light?” Ryuk said. “Are you alright?”
“I’m fine,” he snapped. “I’m just…it’s a human thing. I’m in pain.”
“Why?” Ryuk asked.
“It doesn’t matter. I’ll explain later,” Light said. “I need to go to the bathroom.”
“Then why aren’t you going?” Ryuk asked.
“Leave me alone!” Light said. “I need to mentally prepare myself to get up. You wouldn’t understand.”
“Ok, then.” Ryuk turned away, put off by Light’s abrasiveness.
Ok, Light, he thought to himself. You can do this. The longer you wait, the more likely it is that your sheets will end up stained. The longer you wait, the longer you’ll have to suffer without ibuprofen. So just get up. You’re a man. You can handle this. Men used to go to war! You’re not going to be defeated by some stupid cramps. You’re better than that.
Finally, Light managed to stumble out of his bed. He took a look at his sheets to find that they were thankfully still clean. Then, Light took fresh pairs of boxers and briefs from his underwear drawer.
Light made his way to the bathroom where he cleaned himself up, stuck a pad to his briefs, and pulled his clean boxers on top. He washed his hands and rinsed the blood from his soiled underwear, trying not to dwell on how humiliating this experience was. Someday, testosterone might be able to stop his menstrual cycle. Until then, he would persist. He could do it. His eyes filled with tears.
Light slammed his fist against the bathroom counter. He hated how easily he cried during this time of the month. It made him feel like a weak little girl. It’s fine, he assured himself. It’s normal to tear up when you’re in pain. Men cry, too. Sure, they do. Men who have vaginas and tits and XX chromosomes and childbearing hips and goddamn it his life is so unfair.
Light took a couple of pills from the medicine cabinet and washed them down with water from the bathroom sink. He was probably supposed to take the medicine with food, but he didn’t really care anymore. Finally, Light returned to his room and flopped onto his bed.
It was six o’clock in the morning. Light didn’t have to get up for school until seven. It would be best to try to get another hour of sleep. But he knew that he couldn’t. Not when he was so damn uncomfortable.
“Light?” Ryuk asked. “Are you going to explain the human thing to me now?”
Light would rather not give a crash course on periods to a god of death, but he knew how much Ryuk enjoyed learning about human matters. Getting on the Shinigami’s good side could prove to be useful later on.
“You know how humans reproduce, right? A man’s sperm attaches to a woman’s egg, and that becomes a fetus. The fetus grows inside an organ called the uterus.” Light began to explain.
Ryuk gasped. “You’re pregnant?”
“No!” Light shouted. “Don’t say that, that’s disgusting.”
“Sorry,” Ryuk replied. “I’m just not sure where you’re going with this.”
“Well, why don’t you shut up and let me explain?” Light sighed. “Anyway, if a person who has a uterus doesn’t get pregnant, the uterus sheds its lining. Because it builds up a lining in preparation for a potential fetus. But if there is no fetus, there’s no point, so the body disposes of that lining and the unfertilized egg. And a bunch of blood and tissue and stuff comes out of the vaginal opening and the uterus squeezes itself to get rid of it all and it hurts like hell.”
“That sounds awful,” Ryuk said.
“It is,” Light said. “And it happens every fucking month. And my back hurts and my head hurts and I feel sick to my stomach and it fucking sucks.”
“Wow. Humans have it rough. I assume you’ll be staying home from school, then, since you’re sick?” Ryuk asked.
Light laughed. “I wish. Being on your period—that’s what it’s called, a period—doesn’t really count as being sick. People just tell you stuff like ‘Oh, it’s just part of being a woman!’ Which is stupid because first of all, I’m not a woman. And second of all…fuck you.”
Light turned to lie down on his stomach, hoping the position would ease his pain. “I don’t want to go to school. I don’t want to be in pain. I hate it, Ryuk.” Light’s voice cracked. “It makes me feel like a woman even though I know I’m not, it just…it’s so stupid! Fuck my stupid baka life!”
A pathetic sob escaped from Light’s mouth. He forced himself to even out his breathing. “I’m just so angry!” he complained. “I feel like I could kill someone.”
“You can,” Ryuk reminded him. “With the Death Note.”
Light gasped. “Ryuk, you’re a genius!” He reached towards his desk. “Could you hand me my Death Note and pen? And turn on the TV for me?”
“I guess,” Ryuk replied. “I’ll only do it because it’s quite interesting to see you in this state. You're acting pretty different from usual.”
“You sick fuck!” Light snapped. “You’re deriving entertainment from my suffering?”
Ryuk smirked. “Says the man who kills people for fun.”
Light sighed. “I guess you have a point.”
Light laid on his side and spread out the Death Note on his mattress next to him. He got to work writing the names of every violent criminal he saw. When he ran out of names, Light moved on to those who had committed minor misdemeanors.
Everyone needed to die. If Light had to be in pain, then the entire world should be, too. Stupid criminal scum! Stupid cisgender men with their lack of uteri! When Light came across occasional female criminals, he decided to keep them alive. Maybe he’d kill them later, but for now they could be spared. At least they understood his plight to an extent.
After twenty minutes of murder, Light felt himself getting sleepy. His pain was still present, but had reduced in severity enough for him to feel somewhat relaxed. Light held up the Death Note and pen to Ryuk.
“Put these away for me?” he asked.
As soon as Ryuk took Light’s Death Note from him, Light closed his eyes and drifted off to sleep.
This practice became part of Light’s monthly routine: when his cramps got bad, he would go on a killing spree with the Death Note. It was a wonderful outlet for his frustration.
Several months after Light had his first cramp-fueled killing session, L invited him to join the Kira task force. Light joined L and the rest of the team in a hotel room where L presented Light with a series of graphs.
“This data represents Kira’s killing activity over the past few months,” L explained. “Do you notice a pattern, Light-kun?”
Light had to keep himself from laughing with glee. Although it wasn’t part of his original plan, his monthly habit also served as a wonderful protective measure against him being exposed as Kira. If L was implying what Light thought he was, L noticed that Light’s killing pattern lined up with a menstrual cycle, meaning that the investigation team would think Kira was a woman and therefore not Light.
“Yes, there does seem to be a pattern,” Light said. “Around every twenty-eight days, there’s a period of time—five days, on average—where the number of murders significantly escalates.”
“That’s right,” L agreed. “Do you think this could give us a clue about Kira’s identity?”
Light nodded. “I believe so. This pattern strongly resembles that of a woman’s menstrual cycle. Therefore, it’s very likely that Kira is a woman, and her kill count fluctuates due to hormonal changes that impact her mood and decision making.”
“Your deduction skills are truly impressive,” L said. “That’s exactly what I was thinking. To be honest, I already shared my theory with the task force before you came in today. I wanted to see if you’d be able to connect the dots as well, and you did so splendidly.”
Light beamed with pride.
“Would you mind stepping into the hall with me for a moment?” L asked. “I’d like to speak with you in private.”
“Of course.” Light got up and followed L outside.
After putting some distance between them and the hotel room, L spoke. “I don’t usually go around telling people this about myself, but I want you to know that I’m a transgender man. The task force doesn’t know, but I trust you enough to tell you. I honestly think of you as a friend, Light-kun.”
“Thank you for trusting me,” Light said. He wasn’t quite sure where L was going with this.
“I’m only telling you this to give you context for what I’m about to say next,” L continued. “Because of my position, I’m more than aware of the fact that many transgender men also have menstrual cycles. Therefore, although it is very likely that Kira is a woman, we also can’t rule out the possibility of them being a transgender man. What do you think, Light-kun?”
Light smiled politely. “Good thinking, Ryuzaki,” he said. “I agree.”
On the surface, Light was perfectly calm. But inside, he was raging. He was so angry, he felt like he could kill someone! If only he could kill L…