When It's Forbidden

Summary: Tsuna, a pure angel, falls in love with Enma, a human. But when Enma rejects him, Tsuna makes a deal with the devil, and becomes corrupted. Afterwards, he sacrifices himself for Enma. Character death, some genderbender, slightly dark. Oneshot. 0027, implied G27.

Disclaimer: Katekyo Hitman Reborn does not belong to me! If it did, a lot of questions would be answered…

Me: So. Another Vocaloid-inspired story that is sort of a songfic. This one's based on Alluring Secret~ Black Vow~ by Kagamine Rin/Len. (Who else?)

Tsuna: …so I get killed in this story.

Enma: I'm sorry Tsuna-kun…

Giotto: I really don't like my role in this story.

Me: Tsuna and Giotto, you're both plot devices. Enma, just bear with it. Anyway… let the story begin!

It's a really, really long way down when you're falling down from heaven.

And it's really, really painful when you finally hit the ground.

"Are you all right?" An alarmed voice broke through the darkness.

Tsuna opened his eyes and sat up. He had fallen a long, long way down from the sky. His clothes were torn and dirty and his wings had lost a lot of feathers.

"Are you hurt?" The same voice said.

Tsuna turned his head towards the owner of the voice – and found himself hypnotized by the most beautiful eyes he had ever seen.

Tsuna stared dumbfounded at the red-haired boy who was stretching out a hand. The boy was smiling kindly at him and with no fear at all, even though Tsuna had a pair of wings sprouting from his back.

Hesitantly, Tsuna reached towards the outstretched hand and grabbed it. The boy smiled and pulled him to his feet.

"My name is Enma. You?"

"My name is -"

Tsuna stared down at the sleeping figure of Enma.

If I was a human, we could love each other…

Love between a human and an angel is forbidden. It's written in the sacred book of law.

And yet…

"This is my fiancée, Crystal. Crystal, this is Tsuna. He's staying with me for awhile." Enma introduced them to each other.

"Hello." Crystal greeted Tsuna politely.

"…" Tsuna almost burst from jealousy, but in the end, he said nothing.

"Crystal and I are going to look at wedding clothes, so could you watch the house, Tsuna?"

"…" Tsuna was red in the face by now, so he kept his head down and nodded.

Enma smiled and walked out of the door.

Night had fallen again.

The door swung open and Enma poked his head in. "Tsuna? I'm home! I bought dinner!" He entered the house to find it pitch-black.

"Tsuna…?" A white hand reached out from the darkness and grabbed the back of Enma's black jacket.

Enma screamed silently as he found himself kissed roughly by a figure in white.

Tsuna.

Enma tore his lips away from Tsuna's the blood from his injured lip dripping down his chin. He pushed Tsuna away and looked at him in horror.

"Tsuna… I… you… why?"

Tsuna smiled bitterly. Love between a human and an angel is forbidden…

"You… I have a fiancée… And you kissed me…" Enma's eyes widened as Tsuna suddenly disappeared in front of his eyes, leaving a single white feather shining in the darkness.

Somewhere behind a dark wall, Tsuna cried silently.

Angels have a useful ability: they can teleport.

Crystal beamed at Enma. "Today's the day, Enma!"

Enma managed to nod and smile at her. He had this feeling that he had done something wrong, but he could not figure out what it was.

Crystal adjusted her wedding gown, beaming. The both of them were in a church, preparing to get married.

"Crystal, I… need to go take a walk first. Wait here for me." Enma muttered.

Crystal looked puzzled but shrugged, which meant if you want to.

Enma walked out of the church, trying to figure out why he felt like he had done something wrong, when he heard a voice.

"Hello."

Enma looked up – and found himself hypnotized by the saddest eyes he had ever seen.

"Nice to meet you." The girl smiled. She had waist-long brown hair and sad brown eyes.

Enma blinked. His fiancée was in the church behind him – and yet all he could think about was this girl with the sad, sad brown eyes.

I want to… I want to hold her and make those sad eyes happy.

"My name is Tsunako. You?"

"My name is -"

Crystal tapped her foot impatiently. Enma was really late. She frowned and looked out of the window to see if he was back.

Through the window, Crystal could see Enma running away with an unknown girl.

"ENMA!"

"Make me human." Tsuna looked steadily at the demon.

The demon smirked. "It'll be painful, You would have to cut off your own wings."

"It doesn't matter. Make me human. A female human."

The demon took out a viciously sharp knife and looked at Tsuna's pure white wings.

"Shall we begin?"

It was night time again.

Tsunako smiled down at the sleeping Enma. She reached down to stroke his cheek when she noticed that his skin was icy cold. She frowned and left the room to find a blanket.

After Tsunako left the room, Enma sat up. He was feeling guilty about betraying his fiancée, but he couldn't explain why he had instantly fallen in love with Tsunako the moment he met her eyes.

He also couldn't explain why he had the feeling he had seen her somewhere before. Who did she remind him of…?

The door suddenly opened. Enma looked up, expecting to see Tsunako.

Instead, an angry looking man with golden blond hair and burning orange-gold eyes stood there glaring at him. He was pointing a long-barreled gun at him.

There were pure white wings on the man's back.

Before Enma could react, the angel fired the gun and the bullet penetrated Enma's heart. The redhead died instantly.

The angel glared at Enma's dead body, saying: "That's for stealing Tsuna from me." Then he vanished.

Minutes later, Tsunako came into the room, holding a thick blanket. She stopped when she saw Enma lying cold and dead on the ground.

She rushed over and knelt over the redhead. Her face twisted in pain and shock when she saw the wound on Enma's chest.

My love, lying dead…

Tsuna laid Enma gently on the ground. She knew what to do.

I will spend all my life with you as I swore to that day…

Her tears fell as she placed a hand over Enma's wound.

My sin against God for loving a human…

Instantly the wound began to heal. Tsunako was healing Enma's wound.

All my acts of treachery should be paid by my death.

If Enma was to be revived, Tsunako would have to sacrifice her life.

So I will die for you…

Enma's eyes began to open.

I believe, that's my fate.

The first thing Enma saw was Tsuna, who was a boy again. In that last moment, Tsuna had sacrificed himself, breaking his transformation into a girl.

Tsuna smiled one more time – and vanished away, leaving a single shining white feather.

Enma lay crumpled on the ground, clutching the white feather. As his tears fell, he kept whispering the same sentence:

"Love between a human and an angel is forbidden…"

Me: So done and done.

Tsuna: I hate you Author.

Enma: …

Giotto: If you weren't a girl, I would…

Me: *ignores* so, read and review~!