They tell me to unlock this door

Vash holding him by one purple-clad arm, Gilbert by the other, Roderich is being dragged through his stately home, the heels of his clean shoes leaving lines in the carpet. Roderich doesn't struggle against the two stronger men, but instead tries to smile calmingly at Liliya as she follows closely behind them. Ludwig is leading the group with Feliciano swinging from his arm. Lovino, and probably Antonio too, are apparently nearby as Lovino shouts at Ludwig to get away from his little brother.

Curiosity becomes a scream; what could be behind it?

Gilbert and Vash drop Roderich unceremoniously on the floor, his back dropping against a big, heavy-looking wooden double-door, the tails of his old-fashioned jacket crumpling against the carpet. Two lines stretch away from the doors, showing that the doors were open for a long time, a few years at least. The carpet is well-worn from being walked in and out of multiple times daily. There is a strange smell in the air, like meat that has been left for several days, the stench getting stronger nearer the doors.

Behind this door stands a piano

"This is your piano room," Gilbert says plainly.

"Yes, it is," Roderich answers, not bothering to grace the albino with eye contact.

"Why is it locked?" Gilbert asks.

"Because I locked it."

"Why?"

The keys are dusty, the strings are out of tune

"It's out of tune. It didn't sound right when I played it."

"But you know how to tune a piano!" Feliciano exclaims, "You taught me and Lovino and Elizeveta how to do it! Come on; unlock the door and we can tune the piano and you can play a song and you won't be sad anymore!"

Behind this door she sits at the piano

At his wife's name, Roderich breaks down. He curls up into an impossibly tight little ball of purple, buries his face between his knees, and cries. Gilbert sends Feliciano a cold, murderous glare. Liliya steps closer to her brother, who wraps his arms around her in a mixture of protection and comfort. Lovino snaps at Feliciano in Italian, Antonio hugging the firey Southerner in an attempt to calm him down. Feliciano clings even tighter to Ludwig.

But she plays no more, oh, that was so long ago

Gently prising Feliciano off of him, Ludwig crouches down in front of Roderich's trembling form, "I know you miss her, but you have to try to find happiness. For her, at least."

"I don't see what this particular room has to do with it!" Roderich snaps.

"Playing the piano makes you happy!" Feliciano says, "Doesn't it?"

There, at the piano, I listened to her

"It used to," Roderich mumbles.

"What changed, Mister Edelstein?" Liliya asks.

Roderich raises his head, a soft, sad smile gracing his tear-stained face, "Elizeveta would play the piano, too."

And when her performance began

"She practised often, but usually when I was out. When I was in the house she would play purposely badly; partly to get me to spend time with her, partly to have me fooled that she was a bad pianist. She really did have me fooled, too."

She took my breath away

"It was our anniversary when she sat me down on the piano stool next to her. Unlike every other time I'd seen her play, her posture was perfect. She was sat properly, her wrists were held high, she was smiling and she looked simply beautiful. And then she started to play, and I could have collapsed to the floor she was that amazing. It was clear from her robotic fingers and wandering eyes that the music hadn't naturally to her, that she had spent hours upon hours perfecting the piece, and I simply loved her more than I had ever thought possible."

She said to me "I will always be with you"

"That's beautiful, Mister Edelstein," Liliya breathes, "It's okay if you don't want to open the door, we understand."

"No, we have to unlock the door," Ludwig says impatiently.

"I don't want to," Roderich argues.

But it only seemed she played for me alone

"Please, Roderich," Ludwig says, slowly reaching his hand out, "Give me the key. You don't have to go into the room."

"Why do you even want to?" Roderich cries.

"Can't you smell it? There's been a weird smell emitting from behind that door for weeks now. I need to find out what it is, and deal with the source of it."

I poured her blood into the fire of my blood

"Flowers, probably," Roderich says dismissively, "I put flowers in there before I locked it up."

"Rather strong smell for some pansy-ass flowers," Gilbert mumbles.

"Whatever it is, it needs removing," Ludwig speaks loudly to over-talk his brother's comment, "And we can put some fresh flowers in, yeah?"

I locked the door, they asked after her

"Tulips," Gilbert says glumly, "She was fond of tulips."

"Really?" Vash asks, "I thought it was poppies; she always had poppies in her hair."

"No, tulips, she prefers tulips," Gilbert says, "I'm growing some; I'll go pick a bunch."

"How do you know about the tulips?" Roderich asks suddenly.

There, at the piano, I listened to her

Gilbert pauses for a few seconds, thinking, then shrugs.

"She told me her favourite flowers were tulips, but I was her husband; it was my responsibility to know all about her and her favourite things. Why did you know?"

"Geez, fancy-pants!" Gilbert holds his hands up in defence, "I was her best friend, remember that? From before you went all cuckoo-bananas?"

And when her performance began

"Cuckoo-bananas?" Feliciano asks, concern lining his young face, "What do you mean, Gil?"

Glancing around at an array of confused, inquisitive and curious faces, Gilbert explains; "A couple of months before Elizeveta disappeared, Roderich was behaving weirdly."

She took my breath away

"He was going out less and less. Hell, he rarely left the house. He would insist Elizeveta stayed in the room with him, and if she went anywhere herself he would follow her. He was completely disregarding her personal space and privacy, and whenever she protested he completely ignored her.

Roderich gives a grunt of disagreement. "You're ranting about her privacy, but a wife shouldn't be hiding anything from her husband."

"No, but there are matters of hers that don't actually concern you."

There, at the piano, I stood beside her

"Where the hell did this paranoia even come from?" Lovino demands.

Roderich sighs, resting his head back against the door, "You see… well… she… she was cheating on me."

"What?" Antonio screeches, "That's ridiculous; Elizeveta would never do that!"

"Well, she did."

"How do you know?"

It seemed she played for me alone

"When I left to the performance hall, her clothes were tidy and our bed was made, but when I returned, her clothes were changed and the bedding had been changed. Every Saturday that happened."

"I'm sure there's some sort of reasonable explanation," Antonio says, "Maybe… maybe she gardened on a Saturday, because someone's got to look after the garden, right? Her clothes would have got dirty. And the bedding has to be changed at some point. Did you actually catch her with this supposed other man?"

"Well… no."

The door opens, oh, how they scream

"I'm going to put this simply," Ludwig says, standing, "If you don't give me the key, I'm breaking the door down."

"No!" Roderich leaps up, fisting the front of Ludwig's clothes, "Just leave it alone!"

"I have to sort out that smell!" Ludwig barks, "Key, or I break the door down."

Roderich stares the stoic blond in eye for a few seconds before slowly shaking his head, "No. I can't."

I hear Mother pleading, Father is beating me

Gilbert dragging Roderich out of the way, Ludwig charges once, twice, thrice, four times. The door breaks on the fourth blow, Ludwig cursing as he falls through, landing awkwardly on his elbow and shoulder. The rest of the group cover their noses and mouths as the stench thickens.

"Mein Gott," Ludwig mumbles.

Feliciano skips into the room, hopping cautiously around Ludwig and the broken door. He freezes drinking in the scene painfully slowly. Then his jaw drops, and an ear-splitting scream escapes his tightening throat.

They take her from the piano and no-one believes me here

One by one, the group finds themselves being drawn into the room. Vash freezes, paralysed. Liliya collapses to her knees, garbling incoherently in a mixture of languages. Lovino yells and starts throwing objects around, only to be subdued by Antonio, who clings to the violent Italian, crying into his shoulder. Feliciano keeps screaming, Ludwig hugging him from behind but not even trying to stop him screaming, transfixed by the scene. Gilbert instantly turns and punches Roderich directly in the face.

That I am deathly ill from sorrow and the stench

Roderich falls to the floor, curling up into a ball in a fruitless attempt to protect himself, but Gilbert keeps attacking. Thick, heavy boots collide with his stomach, ribs, arms and spine, shouts and curses in a mixture of German and English falling from above. Roderich's shins and arms make sickening snapping and crunching sounds, his hands and feet going numb, and blood is coughed up from his lungs, dribbling over his lips and cheek. Eventually, in a tear-blinded rage, Gilbert lifts his armoured foot and brings it down on Roderich's head. The sound of Roderich's skull splitting open is indescribably gut-wrenching.

There, at the piano, I listened to her

Gilbert pads into the room, leaving a trail of bloody, grey-matter-filled footprints. He scoops the rotting corpse up from the foot of the piano, ignoring the grotesque smell and the peeling skin of the once-beautiful face he had known and loved. "We can give you a proper burial now, Eliza," he says to his lost friend, "Won't that be nice? And we'll plant tulips on your grave- we'll set Bella and Lars on that. And you can have poppies too, because you were fond of those, weren't you?" Gilbert steps over Roderich, leaving him to be dealt with by someone else, as he carries Elizeveta out into the garden to bury her himself.

And when her performance began

After Elizeveta and Roderich have been buried, and Gilbert has rung the authorities to inform them of the deaths and honestly hands himself over, Lovino approaches Ludwig.

"Hey, potato-bastard," he says, "If you like, there's plenty of space back at my home. Y'know, where Feliciano used to live before he met you? I wouldn't wanna be here after this…"

Ludwig nods gratefully, "I really don't… we're selling it. I'll find somewhere else for me and Feli to live."

"It's okay," Lovino interrupts, "You can live with me and Antonio. I've kinds missed having my ditzy fratellino around the house. And I'll put up with you. Somehow. Just don't wake me up when I'm having a siesta, dammit!"

Ludwig laughs weakly, "I'll keep that in mind."

She took my breath away

Within three days, Ludwig and Feliciano have packed their bags and left. Two days after them, Vash and Liliya are also gone, moving far away. Roderich and Elizeveta's belongings are distributed between the relevant people, as written in their existing wills. The piano is left in the room, as no-one wanted it. The door is repaired before being handed over to the market for purchase, and the former residents leave forever.

There, at the piano, she listened to me

A year later, the house has been purchased by the rising-in-wealth Kirkland-Bonnefoy family. 'Papa' Francis has fallen in love with the beautiful old house. 'Daddy' Arthur likes the garden, and the little patch of poppies and tulips in one corner. Children Alfred and Matthew are looking forward to exploring the huge house and playing hide-and-seek, Alfred being convinced that such an old house will have dozens of hidey-holes and secrets.

And as my performance began

Francis is grocery shopping. Arthur is gardening, planting more tulips and poppies, and adding roses and chrysanthemums. Alfred and Matthew are exploring when they hear soft, beautiful music drifting through the house.

They follow the music to a door that, if they had been older and more aware of their surroundings, they would have noticed it is significantly newer than the rest of the house. They would also have noticed the dark stain in the carpet, but neither child does as they push the door open.

At a piano sits a man dressed entirely in purple. His smart clothes are crumpled and bloody, and his arms and legs are at odd angles, but he still somehow plays flawlessly.

I took her breath away

The brothers watch with wonder their young ages giving them the innocence, ignorance and curiosity to let them edge closer to the mysterious man. The song continues as the boys climb onto the piano stool. Neither notices the bloody face of the man, his caved-in head, too distracted by the uncovered strings of the grand piano that they are now able to see.

The song ends on a sustained chord. Alfred turns to ask the man to play another song, to find that he has vanished, a single purple tulip placed on the cushion he had been sitting on.

The bolded lyrics are Herzelied's translation of Rammstein's Klavier, with some phrases edited slightly to better fit my understanding of the song(but are still accurate)

I'll leave it up to your preferences and headcannons as to whether Elizeveta was cheating on Roderich or not.

I don't own Hetalia, or Herzelied, Rammstein and the song Klavier
-Laurel Silver