I come bearing my first short story here on FictionPress. This is actually an entry to a local writing contest, so some concrete criticism would be great!
Note: God is used as a plot tool in this short story. If you dislike that, please don't let it interfere with your reading experience. God, I sound like an insurance lady. D: Also, heart transplants from live donors are not possible OFFICIALLY. Make of that what you will.
Enjoy!

Sand Letters

At a harbor in a town that was set beside the sea, a young girl sat alone and still.

Afternoon sunlight spilled across the yellowed sand beneath her bare feet, painting it and her hair an evanescent gold. She was dressed in a simple white smock, a thick woolen quilt draped across her shoulders; honeyed locks brushed the back of her neck with each tiny gust of wind as she stared, stared, out at the churning violet sea. The girl paid no heed as the tide pulled in and soaked her dress, swallowing her legs in thick white foam—instead, she curled them closer to her chest and dug her fingers hard into the wet-filled sand.

"Dear God…how have you been?"

She bit her lip, and smiled.

"God, it's been a year."

The tide swept back, drawing shells and pebbles into its enveloping grasp; with it, her smile washed away into a faded, brittle ghost.

"…It's been a year."

It had been a year.

Countless people agreed unanimously that they were a remarkable pair of twins, and they certainly weren't wrong; Jen and Vin Sergeant, as one unit, were a force to be reckoned with, no matter the circumstances. Jen personally believed it to be because of their names, since her full name was Jenevieve, a derivative of the name of King Arthur's wife, and her brother's Vincent, "one of the Knights of the Round Table". She'd thought this, until Vin one-upped her by stating that it was Guinevere, not Jenevieve; that Vincent was never one of the Knights; and that her recollection of names was the most horrifying thing he'd ever witnessed. She had beaten him after that. Names aside, however, they truly were unlike any twins ever seen in their tiny town by the sea.

"Obviously, it's because we're magical," Vin said matter-of-factly, and Jen snickered in agreement.

Perhaps people admired them so because of their similarity in appearance. Vin, by no means, looked like a girl, and Jen hadn't a single boyish trait in her, but there was something about the way their hair fell, or their identical, light brown eyes, that made passersby stop and exclaim; "Well, I don't want to believe it, but I think there's two of them!" To prevent any embarrassing mix-ups, Vin tied his hair in a ponytail at the back of his head—he wore his hair long, the same length as Jen's, but was able to charm the school officials into overlooking it, and eventually stopped people from talking about it at all. That was how the twins worked: Jen would devise a scheme, and Vin would act upon it, with both of them sharing the rewards and benefits once all was said and done. They were a team, two halves of the same whole; between them, anything was possible.

"Jen and Vin, the Wonder Twins," Vin whispered at night, and Jen, in her cot beneath him, nodded happily.

Once, when they were barely six, their parents took them to the seashore.

Even though the Sergeant family lived in a neighborhood only ten minutes from the public beach, life was such a convoluted hassle that nobody could find time to take a vacation in their own hometown. This visit was the first time Vin and Jen had ever been to the beach, so as soon as their feet touched gritty, grainy sand, they were off. Sand castles were built, splash wars were won and lost, games of tag were held across the stretch of coastline. Evening came, and within the watchful gaze of Mumma and Dad, they settled down at the very edge of the shore, letting soft waves lap at their toes. Vin chattered on and on about the seagulls overhead, but Jen, in contrast, was unnaturally silent. Finally, she lifted her head from her arms and said plaintively, "Vin, is God real?"

Vin stopped mid-word to gape at her. "Is God real? Wha'da'ya mean, is he real? 'Course he is! Mumma said so."

Jen laid her chin on her folded hands. "But I saw a bunch'a big kids when we were in the water, and they were sayin' that God was bad, an' that people who believed in him were stupid." She sniffed. "Mumma said stupid was a bad word, and I don't wanna be stupid…"

"They're stupid!"

Her eyes widened at Vin's sudden vehemence. She could only stare as he leaped up, stretching his hands to the clear and cloudless sky.

"God's bad? No way God's bad! God made the sky, an' the beach, an'—who could hate the beach? God made the beach for everyone to be happy!" He twisted his head back to show her a sudden, blinding grin. "How can a God who made a whole bunch'a beaches for everyone to play on be bad?" He fell to his knees in front of her, clapping his hands on her knees and leaning close. "That's why I say God's real. 'Kay?"

Jen kept staring, and then slowly nodded, scrubbing her eyes with the back of her hand. " 'Kay…" She gave him a wobbly smile.

"Hey…I have an idea!" Vin grabbed her hand and yanked her to her feet. "We're gonna leave God a letter!"

"A letter? How?"

"Well, see…" Vin scratched his head, then brightened and stabbed his toes into the sand. "We're gonna write it in the sand! And then, when the sea comes and the letter's gone, that means it's gone to God!"

Jen did the same, hop-skipping in a circle to carve an arc with her foot. "But Vin, we can't write good. How's God gonna know what we're saying?"

Vin chewed on his lip, thinking hard. "Uh…huh. Problem. Well, we can just leave our name! He'll still know what we're talking about." With that said, he set about his work, ignoring Jen in face of the task at hand. After a few minutes, she began to work too.

By the time Mumma and Dad came to gather them up for the trip home, the tiny patch of beach they occupied now displayed a huge heart, with "V" and "J" proudly scratched in the center. The twins watched, with matching grins, as the tide came in, and washed their letter into the sea.

Despite all the human aspects twins normally shared, there were some things that just couldn't be, and Vin made it clear to anyone who asked that he loathed it.

Vin had a strong, healthy heart. Jen didn't.

Since they were fraternal twins, some genes were distributed unevenly, and Jen was cursed with a heart that worked itself too fast and too hard when it shouldn't. Her condition made itself more and more evident with each passing year, and by the time the twins were thirteen, she paid regular visits to her specialist, Dr. Tanaguchi. Vin could never go with her. Instead, he waited in the hallway outside, folding bits of old magazines into a paper menagerie of tiny animals to present to her once her check ups were over.

Jen couldn't understand why he did what he did. Vin had friends, activities, even a reputation outside of her; why did he spend every day that she had an appointment waiting for her with such a quiet, sad face?

One night, when she couldn't take it anymore, she asked him, "Do you feel guilty?"

He glanced up from his dog-eared copy of A Tale of Two Cities with a bemused look. "There's a whole lifetime of things I could feel guilty about, and ninety-six percent of those things should make you guilty, too, since you planned them."

"I don't mean that."

She tiptoed her way to the empty side of his bed, crawling in it and shuffling beneath the covers. Vin sighed, tossing his book on a pile of laundry and shuffling under the covers too. Soon they were situated in the same position they slept in as children: foot to foot, hand to hand, forehead touching forehead, with their hair splayed in a single, golden halo. Vin flicked the lights off, and Jen whispered, "My heart problem. Do you feel guilty about it?"

Her brother was silent, but she knew he was thinking, and it wasn't long before he softly admitted, "Maybe."

"But it's not your fault! I was made this way; you had nothing to do with it. Nothing at all."

"Maybe so…" Rough fingers carded through her hair; she closed her eyes, still listening. "Maybe so, but I'm the younger twin. I was born fifteen minutes after you. It's always the younger twins that get the medical problems, that's how it's supposed to be."

"This time it was the older. Things like this happen."

"But it should've happened to me, not you!"

She opened her eyes to meet Vin's. They were ablaze in a noiseless, righteous fury—righteous for her, righteous for them, righteous for the should have's and would have been's that would never be. They blazed, and she didn't know why.

She didn't want to see them anymore.

"Hey, Vin…we should go write a letter."

Hearing this made Vin's blaze die down, a little, and he breathed. "…A letter. You're right. We haven't written one in awhile."

Jen nestled up close to him, watched as it simmered down with the seconds that passed. "Think that corner of the beach is still free?"

"I'm sure it is."

The blaze died, Jen closed her eyes again, and the night was peaceful.

Once Jen was drifting deep in sleep, Vin pressed a kiss to her forehead. "I'm going to make things the way they're supposed to be, Jen. That'll be my letter tomorrow.

"And God's gonna answer it; just watch."

Fifteen was the year when something began to change between them. It was subtle, to where neither twin recognized it for what it was, but both could just tell by the signs: a rift was making itself known, in the form of the age old debate of love versus dreams.

A new pair of twins, brothers, had moved to the tiny town by the sea from frozen Romania; they went by the names of Karlis and Seimohn Vendal. Jen, for her part, had no clue that she would fall for one of them, but fall she did. Karlis felt the same, and within a few weeks, they were dating. As for Vin, he found a kindred spirit in Seimohn; both had high goals that would make use of their intelligence, and soon they were drawing out plans together, building an empire on paper. A short time later, it was clear that Jen became wrapped up in her love for Karlis, and Vin was engrossed in his plans for the future—and it was a long, long time before they went to leave letters in the sand again.

It was a Friday, two days before their sixteenth birthday, when Jen and Vin paid a visit to their corner of the beach at last.

Vin wore his hair down that day, so that it curled at his shoulders; he and Jen had decided to get identical cream-colored streaks dyed in their hair, eliciting several strange looks. When asked why, they both simply beamed, "We're the Wonder Twins, duh! We need a trademark." With that logic, no one asked again. Because of that, they didn't see the awkward look the two shared, before they quickly turned away.

Now both were standing on a dune, in bikini and swim trunks, with the sun dipping into the cobalt waters and melting into an aureate stream of light. It was a beautiful sight, but neither was truly appreciating it. Jen sighed and adjusted her straps; Vin rubbed the back of his neck, fingering his hair.

Silence stretched, and silence grew.

"…So. Um." Vin flicked his eyes at Jen. "Did your date with Karlis go okay?"

She clasped her hands behind her back. "Mmm-hmm. He's such a sweetheart." A tiny smile lit her face. "I started having some trouble, but he was so nice and got my meds for me when I couldn't—"

"What? You had another episode today?"

Vin laid his hand on her shoulder, and Jen shrugged it away, glaring at him. "Yes, I did. But I'm fine now."

He frowned in concern. "But…"

"But nothing! Ugh, why are we here anyways? This 'writing letters to God' thing. It's stupid." She kicked at a mound of sand. "We're older now. We're grown up. Who does this stuff, anyways?"

Behind her, Vin lowered his eyes to the ground. "Well…we do."

"No, Vin. You do." Jen turned on her heel and headed toward the car they shared. "I'm going to call Karlis."

"No you're not! We haven't written a single letter in almost a year, the least you can do is leave a note!" Vin followed her, matching her stride for stride. Jen scoffed.

"There's nothing to say. You just hurt yourself worrying about my condition, and God never answers anything we leave behind. I'm better off telling Karlis my problems."

"Now hold it!" Vin exclaimed, grabbing her by the arm and jerking her to a stop. "Why are you suddenly against our letters? You've never turned down a chance to come here, not even when you were sick last year. When has…when has Karlis become of such priority to you?"

"Since you and Seimohn started your little 'entrepreneurship' and practically left me behind!" Jen spat, and her brother's eyes widened. "And don't go talking about those letters. On and on, 'we gotta leave a letter today! Who cares if it's raining or if we're busy, we gotta leave a letter!'"

Vin looked hurt; she ignored him, instead twisting her arm out of his hand and marching onward. "Those aren't letters, they're stupid childish habits. God's not gonna answer little words drawn in the sand, Vin, because they disappear. They disappear, just like every other stupid thing in the world!"

She clenched her fists, and the sand suddenly seemed blurry, and her chest felt bursting from pain and why was it getting agonizingly dark—

Jen hit the sand, and Vin screamed.

It hurt. It hurt, it hurt, and Jen couldn't see anything, but she smelled antiseptic and could hear the clang of metal. She heard murmuring, her name, and she tried to answer but nothing would come out but a soundless scream. It hurt.

Voices above her. Mumma? Dad? They sounded so scared. Terrified. Someone else should be there. Who?

Vin?

"Let me do this."

There he was, right beside her; she felt a wave of relief and tried to call out his name. Vin? Vin sounded strange. He sounded determined. Mumma was crying.

"My heart for hers. Let me do it, Mom. Please."

His heart for hers? What was he talking about?

Another wave, this time of excruciating pain, but something slipped into her hand and she realized it was Vin's own. "I told you, didn't I? I'd make things the way they were supposed to be."

His voice faded away; before everything dissolved into black, she could make out the words: "Leave me a letter when you wake up."

When she woke up, Vin was gone.

She was still in recovery when they held the funeral.

It had been a year.

Afternoon bled into evening, and the girl was still there, fingers digging into the sand and making little scratching noises as she whispered to the ocean. "It's been a year, God. How are you doing? I guess you're good, since you're God and all. If you're even listening. If you're even there."

It had been a year, and today was the first day since Vin's death that she'd come to the harbor by the sea.

"If Vin's with you, please tell him not to bother all the other angels, 'cause that's even rude for me. Tell him to build big, gorgeous inventions so Jesus and Moses and everybody else can enjoy them. He'd always liked inventing."

She dipped a finger in a damp patch of sand, and drew it across the grains in an arc.

"Tell him Mumma and Dad think about him every day."

Another arc.

"And tell him…"

She stopped. Without realizing it, she had drawn a heart into the surface of the beach. A tiny 'J' occupied one corner, and in the center—

I'm sorry.

A large wave rushed to meet her head on, spraying her face with salty droplets; she scrubbed at it, biting her lip again, because now a tear stubbornly squeezed itself from her eyes and fell, followed by another, and another. Soon, she was sobbing.

"I'm sorry…"

The wave drew back. A breeze gently ruffled her hair, making her look up. Her eyes fell to the heart, and her own heart—that belonged to someone far more precious than she—stopped.

'I'm sorry' was gone, swept away with the tide. In its place, another message glistened in the sand:

I know.

Jen stared. She looked at the sea, with its angry waves, and then down at the etched words again. After a moment, she dug her fingers in the sand once more. She was smiling.

At a harbor in a town that was set beside the sea, a young girl sat alone and still, trading messages with the twin brother she'd regained—letters, sketched in the sand.

Major super bonus points to whoever can name the song that this story was inspired by, and the song that the first/last line derives from. Hint: Vocaloid. ;D