Got a request from Shiranai Atsune and I decided to write it xD

This story is going to be Guren x Fem!Yuu, Kureto x Fem!Yuu and a little twist, everyone sees Yuu as a boy! Rated M to be sure, don't know where it will go exactly. Enjoy reading! (I'll try to update once every two weeks)

It was an ordinary night. The curtains of the room were closed and Yuichiro Hyakyua laid under her sheets. As usual, she couldn't sleep. She couldn't sleep as long as she was here. After she was rescued, she had trouble adjusting and tried to talk to Guren a few days ago. "Stop bothering me brat. I don't have time for little kids." He was teaching and had just separated the boys and the girls in class. Problem was, Guren put Yuichiro with the boys.

"B-but…"

"Get lost Yuu. Not now." She had just sighed and stood with the boys. He never understood her.

"Alright I couldn't care less!" Yuu had told herself after class. "I wanted to be a boy anyway." Yuu didn't know how it had happened, but everyone saw her as a boy. No one even questioned it. It was outright weird, but she didn't mind. She did mind other things.

Yuu tossed and turned in bed and couldn't but feel a little angry. "No one listens to me!"

"Go to sleep kid."

"WHHAA?!" Guren looked up from his book and looked at the utterly shocked child in front of him. To him, Yuichiro was just an ordinary boy. "What the hell are you doing here Guren?!"

"What does it look like."

"I don't know that's why I asked!" The black haired man sighed and closed his book.

"Babysitting. That's what I'm doing. Since you can't sleep by yourself and you're being a stubborn brat." Yuu pouted.

"You're being annoying and mean." She replied, crossing her arms.

"Go to sleep."

"You can't tell someone to go to sleep. Doesn't work that way."

"What did I do to this universe to deserve this brat….." Guren rubbed his temples.

"Hmmph." Yuu snorted and threw the sheets over herself and turned her back to him.

"Yuu and Kimizuki! If you don't stop fighting now, I swear to god-" Once again the black haired Lieutenant Colonel had to intervene. He grabbed both of them by their hair and hit their heads together.

"Ouch!"

"Detention for the both of you."

"It was his fault!" Kimizuki growled. "Again. So everyone sees me as a dude. Alright then." Yuu thought and smiled. This would work out to her advantage.

"Of course it was Kimizuki's fault! Look at his smug face!" Yuu then retorted, trying to punch the guy.

"Go. To. The. Detention room. Now." Guren warned. He looked like he was about to burst. The two students quickly obeyed. Yoichi and Shinoa looked at them, wondering how many times this had happened already.

"This is your fault. Why must you be such an asshole." Yuu said. They were both sitting in an empty classroom. Kimizuki had placed a book on his face and leaned backwards with his chair. "Hey are you listening to me?!"

"Shut up Yuu, trying to sleep here. You're the asshole."

"You started."

"You did." At that moment Lieutenant Colonel Guren Ichinose opened the door and glared at the two.

"Think about what you've done for the next hour. One wasted hour for me." He sat down and placed his legs on the bureau.

"Why are we doing this." Yuu asked. "Why am I at a school while the whole world is overrun by monsters and vampires?! You should just give me a sword and get revenge!" Kimizuki looked annoyed from underneath his book.

"Not this again." Guren decided to ignore Yuu and resumed reading his book.

"Alright. I'm done. What's the point in wasting time like this?! I need to avenge my family!" Yuu stood up and walked over to the door.

"Where do you think you're going."

"Out." And before Guren could react, Yuu slammed the door behind her.

"What the hell is everyone's problem?! I want to kill the vampires for them!" She put her hands in her male uniform's pockets and growled. "Mika… I want to avenge you. I won't give up." The black haired girl sat down against a nearby tree and rested her head in her hands. Before she knew it, she had fallen asleep against the tree.

"Wake up."

"Hmm."

"Yuu wake up." Yuu felt an object poking her and opened her eyes. Guren was annoyingly poking her against her head with the scabbard of his sword.

"What the hell?" The sky had already turned blood red.

"Go to your room." Guren commanded.

"You're not mad at me?" Yuu asked confused.

"You finally got some decent sleep. It's not like I care what you're doing anyway."

"Why are you here then." Yuu noticed a little hesitation in his eyes.

"Because… Someone will annoy me with you being absent." Yuu stood up and muttered something. "Yuu I'm serious. Go to your room." "Yeah, yeah. Get off my back." Guren clenched his fist but ignored the urge punch the kid in his face.

Once in her room, Yuu felt alone again. "Mika…" She sobbed. She laid under her blankets and Yuu eventually fell asleep. This time without anyone in the room. At least she thought. Guren checked on her every night. Every night, he saw her red eyes from crying or heard her scream when she had a nightmare.

The next day, Yuu walked over to her classroom. She was almost there, but noticed something going on in the hallway. "Hey Yuu!" Yoichi ran over to him and waved. "Hey." "Have you heard? Shinoa said that we're getting our swords today! Guren acknowledged us when you saved me from the vampire a few days ago." "Oh that. Took him long enough. I'm ready to kick some ass!"

Kimizuki, Shinoa, Yoichi, Yuu and Guren entered a dark room below the school grounds. Shinoa hummed as she walked behind the black haired Lieutenant Colonel. "Do you think this is funny?" He asked.

"Not particularly. But I'm glad to see you kept your promise."

"Hmmph."

"Where are we?" Yuu asked curiously.

"A facility below school grounds, duh." Kimizuki replied. Yoichi seemed a little scared and grabbed Yuu's arm.

"I don't like this at all." He muttered. Guren turned around.

"Well, you wanted a sword, so here we are. Pick one and we'll see if you can master the demon inside." He sounded ominous but looked rather serious.

"What if we can't?" Yuu asked.

"You turn into a demon and we'll have to kill you." Guren replied without hesitation. "But if you succeed, you'll have a sword that is able to kill vampires. A sword from the Black Demon Series, just like mine. So don't fail." He added.

"Let's do this then." Kimizuki walked over to a pair of twin swords and stood in front of them. Yoichi stood in front of a bow and Yuu stepped in front of a katana. Without hesitation, she took the sword in her hands.

"Well…. Did not expect you to be a girl…"