A/N: It has been quite a while since I wrote a story, so I hope that this story will be to your liking, but of course there will probably be some people who won't like it. I also need to tell you that English isn't my native language, so I'm very sorry if there are any errors in my story. I don't have a beta, so I have no one to correct the story for me.
This is the prologue and not long after this I will also be placing the first real chapter. I'm currentl writing the second chapter and I will make sure to put that one on here once I'm finished with it. So please start reading and I hope you will enjoy my story.

Summary: Izaya has been hiding the fact that he is intersex for the people around him. One of the people he doesn't want to find out is Heiwajima Shizuo. So what happens when both get drunk at a party and end up at Izaya's apartment together?

Disclaimer: I don't own Durarara!

Intersex is when a person has genitalia from both sexes. In most people the genitalia of one sex will work only, but there are a few people whom have both genitalia which work. Orihara Izaya is one of them.

There are a select few people who know this about him. Kishitani Shinra and a special doctor at the hospital are the people around him who know about it. Of course his parents also know about this, but he doesn't really have a good relationship with them. That's why he doesn't consider them when thinking about who know about this.

On the streets and to everyone around him he acts like a man, because he knew he had to choose between one of the two sexes. Still he uses his other sex sometimes when he works. That's how another person had to know about what he was really like. Shiki-san was one of his most important clients and because of that he told him about himself being intersex. The man hadn't even looked surprised now that he thought about it. Still it had been necessary to continue working with him.

Now there was of course his nemesis Heiwajima Shizuo or Shizu-chan as he called him. He was one of the people Izaya definitely didn't want to find out about this. He guessed that if the guy ever found out about this everything would change and that was something that he absolutely not wanted. Shizu-chan was unpredictable and so he had no idea what the protozoan would do if he found out about Izaya being intersex.

Honestly he didn't want to think about this at all, but every month he had a reminder of the fact that he was indeed intersex. Even though he couldn't exactly say every month since his periods weren't really that regular in comparison to women, so it didn't exactly happen every month. It just so happened that today was the start of one of his periods and he couldn't really say he was happy about it. The menstrual cramps were very painful for him and he just had to have the luck of having run out of his painkillers.

He had told Namie not to come in today since he couldn't even move properly and was currently lying on his couch waiting for Shinra to come with his painkillers. He shifted a few times on the couch trying to get comfortable but the pain was too much to be able to find a comfortable position. This was one of the parts he really hated about periods. Honestly he would rather just stay in bed for the whole week waiting for his period to be over, but he knew that wasn't possible with his work and people would definitely get suspicious if he did it every time.

A knock at the door got him out of his thoughts and slowly he stood up. His legs were shaking quite a bit and he could feel the pain in his lower back too. This was definitely one of the worse periods. He made his way slowly to his door when he heard another knock, this time a lot less patient.

After making it to the door he opened it to find Shinra on the other end of it. He was relieved to see that the man hadn't brought Celty up to his apartment, because that would have been awkward since the dullahan didn't know of him being intersex.

"Shinra…" Izaya said before stepping aside and letting the man inside his apartment. After closing the door he slowly made his way over to the couch and sat down beckoning for the other male to come over to the couch.

"How bad is it this time?" Shinra asked once he had come over to the couch.

"Menstrual cramps, lower back pain, barely able to stand…" Izaya started to list of. "Luckily I haven't thrown up yet." He knew that was always still possible, but he rather hoped that it would stay away this time.

"I get that it's pretty bad this time." Shinra said before taking out the painkillers. "You know how they work. I will get you a glass of water so you can take the pills."

Shinra had already left for the kitchen when Izaya opened the bottle with pills and took two out of it. He placed them in his mouth and took the glass of water from Shinra before swallowing the pills together with the water.

"Will you be fine? Or do you want me to help you get to your bedroom?" Asked Shinra. Even though he meant it well Izaya was never going to accept his help like that.

"I will be fine on my own." He said a little harsh. He could hear Shinra sigh at his words, but the man didn't go further on the topic.

"If you don't need anything I will get going." Shinra said before remembering something. "Oh right, Celty and I are holding a newyears party for everyone, so you're free to come."

Izaya narrowed his eyes at this. "Shizu-chan will be there too right? Do you really think it is wise to let the two of us together in your apartment?"

"Shizuo will be there, but can't you two have a truce for one night? Just till the end of the year? I really want you both to be there." Shinra said. Of course Izaya didn't really believe the last but he didn't see any other option than to go to the party.

A sigh escaped Izaya's lips while he looked at Shinra. "Fine I will be there, but don't come complaining if we ruin the party." He said.

"Thank you, I will make sure you won't regret it." Shinra said at last before heading over to the door and letting himself out.

"I'm already regretting it…" Izaya murmured, before slowly standing up to go to his bedroom. Once inside his bedroom he crawled under the covers before closing his eyes and to try and get some sleep.