Here it is! A Yuki Yuna is a Hero fanfic featuring my favorite couple, Sumi and Sonoko! The story will mostly focus on those two, so don't expect a Yuna-centric fanfic.

I don't own Yuki Yuna is a Hero.

The saddest Sumi had ever felt was when Gin died.

She clearly remembered walking towards the girl, congratulating her on the defeat of the vertexes, and then the awful realization that Gin was no longer with them.

She was dead.

Dead.

Dead.

Sumi's hand trembled as she gently placed her flower on Gin's chest. She now said goodbye to a Hero. Sonoko's hand trembled too, and Aki laid her hand on top of the blonde's. Together, they placed the flower on Gin's chest. The girl's eyes closed for the last time, and Sumi felt her heart grow heavy. It was all she could do not to cry.

Sonoko and Sumi took their respective places, shooting a glance at each other. They waited for the funeral to continue, but everyone seemed to be frozen in place.

"Not at a time like this…" Sumi murmured. A familiar chime ran through the air, and Sumi began to feel the repressed tears fall. "I will…"

"For Mino!" declared Sonoko. She looked at Sumi, and though her eyes shined, there was sadness mingled there as well. "Wasshi, for Mino let's destroy this vertex!" Sumi nodded and transformed.

The vertexes weren't too powerful, but Sumi could feel her strength failing. Without a third member of their team, they were lacking.

"Hiya!" Sonoko rushed after a vertex, her spear at the ready. She flew forward, through the vertex, behind the wall.

"Sonocchi!" exclaimed Sumi, running after her friend. She shot an arrow at the troublesome vertex, but it was already retreating, injured from Sonoko's attack. Her vision went dark for a second as she passed through the wall, but an instant later she stood next to her friend. "What is this?"

Hundreds of creatures joined together, forming a vertex. Sumi stared at Sonoko with wide eyes, taking in the girl's astonishment. She obviously didn't know what this was, either.

"I don't know," the blonde answered honestly. "Is this how the vertexes are born…?" She shielded her eyes as she looked up, towards one of the almost-completed vertexes.

"That's one we fought before," breathed Sumi. "How is this happening?" Sumi turned to leave. "We will get answers." The two departed, leaving no clues in their wake to show that they had ever been there.

The jukai quickly vanished, and Sonoko and Sumi found themselves standing on a bridge. They had vanished from Gin's funeral.

"Mino…" murmured Sonoko. Sumi didn't say anything but averted her eyes. Being absent from the funeral of their dear friend, even if it was to save humanity, felt shameful.

"We have no choice," muttered Sumi. "We have to ask Aki." Despite that, the two lay on the ground for a while, processing what they had seen. Despite her attempts to unravel this mystery, Sumi felt her mind drawing a blank. What could that have been…?

Rain poured down in torrents, wetting their hair and clothes. Droplets clung to the blades of grass, and the flowers seemed to wilt under the rainstorm. Sumi's tears intermingled with the rain as water ran down her face.

"Girls." Aki stood over the two now, an umbrella in hand. "Do you need a ride?"
In the car, Sumi spoke up first. She was drenched but didn't care, not now, not when she needed to find out the secret behind the hero system.

"Why are the vertexes reforming!" she exclaimed. "They shouldn't be coming back! I thought they were gone for good." Aki screeched to a halt, her car's wheels leaving marks on the street. She looked forward for a bit, seeing Sonoko and Sumi's faces in the rearview mirror. "Are we going to have to fight until we die?" Sumi began to cry again, kicking out. "Just like- just like Gin!" Sonoko began to cry as well, and the two hugged. Aki sighed.

"There's new gear," she informed them. "You won't have to die now." She didn't mention that what would happen was so, so much worse.

Sumi was dropped off first, and she settled into bed almost right away. Sleep didn't come easily, though, and she was further distanced away from relaxation when she got a call from Sonoko.

'Wasshi, I don't know what to do.' Sonoko's voice was tinged with desperation, and Sumi frowned slightly.

"We'll see what this new gear is," she said, "and then we'll decide what to do."

'Okay, Wasshi,' said Sonoko, a bit more cheerfully. 'Let's sleep now!' Sumi hung up and slid her phone down to the table.

"No matter what," she said softly, "I absolutely won't let you get hurt."

Phoenix.

Sumi opened her eyes to a dream. She stood in the jukai, without her weapon or phone. Above her was Sonoko, flying in a phoenix-ship.

Lost?

Sonoko fell, one of her eyes dull and her body weak. The vertexes were destroyed, but at what cost?

Loss.

Sumi watched herself in a wheelchair talking to a red-haired girl. But where was Sonoko?

Hospital.

Sumi found herself next to a hospital bed, staring into Sonoko's green eyes.

"Wasshi," she murmured.

"I'm here!" yelled Sumi. "Sonnochi…!" A black haired girl, the mirror image of Sumi, stood on the opposite side, without the red-haired girl this time.

"I'm sorry," said the girl. "I'm so sorry."

Wake up.

There was a hole in the wall.

Wake up.

The redhead was dead.

Wake up.

The mirror girl was a sacrifice.

Wake up.

"I'm so sorry, Wasshi. I forgot you…"

Sumi bolted awake in the middle of the night, eyes wide. She straightened out, sweating and panting. Her breath came out in short gasps, and her skin was clammy to the touch.

"Just what was that?" asked Sumi. She walked to the kitchen and prepared tea as quietly as possible. "Sonoko… what's going to happen?"

What might have been. The Shinju was speaking to her. Sumi stood at attention, nearly spilling her cup. It will not be. I have a new plan, now. Worry not. In the same instant, the voice was gone.

"Did I imagine that…?" Sumi looked around, then dragged herself back to bed, glad to not encounter another nightmare. She had a dream free sleep and woke up feeling refreshed.

She met Sonoko at a bathing site, and the two got dressed as quickly as possible in order to receive new gear. Their phones seemed to be the same, but the creatures which popped out were a new addition.

"Uwahh~ I'm going to name him Sebastian!" Sonoko hugged the powerful weapon and smiled. "What do you think, Wasshi?"

"They don't look strong, but appearances can be deceiving." The two talked on their way home.

"You're right~!" Sonoko seemed back to her cheery self, and Sumi smiled because of that. "Hey, let's have a sleepover!"

"Eh!" Sumi backed away. "What brought that on?"

"Aw, Wasshi! Say yes!"

"What? Don't- Ah, Sonnochi-!"

The two eventually arrived at Sumi's home, brightly smiling. Sumi's, however, held a shadow of doubt. She didn't want to relive her horrible nightmare.

'What might have been,' she reminded herself. 'Will not be.' Sonoko stared at her friend, worried, but dismissed those thoughts.

"So what do you want to do?" The two sat on the floor of Sumi's room, their faerys floating over their heads.

"Eh~ I kind of wanted to write something."

"But remember last time I tried to write…" The two thought back to Sumi's disastrous attempt to write a patriotic novel.

"Let's write about our adventures together!" Sonoko clasped Sumi's hands in her own. "I want to write our story." Sumi gaped, startled, but then she gently smiled.

"All right," she said. "Well, let's start it out with us three girls."

"All right! The kind and reliable Nogi, the serious but sometimes amusing Wasshi, and Sonnochi!" Sumi chuckled.

"The intelligent and empathetic Sonnochi," she firmly corrected. "They were all Heroes."

"Eh? Okay. They defended Japan secretly-"

"Defending love and patriotism!" declared Sumi, quite loudly. "Kokobou Kamen!"

"Yay!" Sonoko and Sumi awkwardly clapped, because Sumi wasn't quite used to it. "They became good friends, right?"

"Yeah." Sumi thought back to Gin and smiled once more. Then she thought of her dream. Just what could it mean?

"So they continue to fight, never giving up, not ever." Sonoko also smiled, thinking back on their battles. "It was hard, but they always came on top."

"Evan if…" Sumi swallowed nervously. "Evan if one of them died, they continued the fight!" There was silence for a while before Sonoko turned to Sumi's computer.

"Yes. They… continued…" A tear fell on the screen. "To fight… to protect their dear friend's spirit!" Sonoko finished typing up the story and presented it to Sumi. "Let's not publish it. This is-"

"-our story," finished Sumi. "Heh, Sonnochi, I really miss Nogi."

"Me too." There was a long pause.

Then they heard a ringing.

"At a time like this!" exclaimed Sumi. "Well, we can test out our new powers." The two transformed and faced the vertexes, all five of them.

Sonoko immediately created a shield and crouched down. Sumi fired an arrow into the first vertex, blowing a hole in its side. Sonoko jumped up, lance at the ready.

"Hiya!" She cut the vertex up, stopping for breath when her task was complete. "One down, four to go!" She jumped up again, sending lances toward the second one. In retaliation, hundreds of fireballs came at her. "Eh?" She created a shield and held her ground.

Meanwhile, Sumi turned towards the third vertex. An arrow pierced it's eye and sent it a few paces back. The brunette jumped over the creature to a better vantage point.

"This won't do anything," she realized. "Well…" Her faery handed her a gun, and Sumi smiled. Bullets pierced the vertex all over, blowing holes all over the creature. It, too, retreated.

"FOR NOGI!" yelled Sonoko, attacking her vertex while it was reloading. It stopped when Sonoko sliced its body in half and began to retreat as well. "Only one left, Wasshi!"

"Let's do this!" cried the brunette.

"MANKAI!"

The two in their improved forms floated side by side. Though she had a horrible feeling in her gut (just what was that dream about, anyway?) Sumi sent hundreds of shots at the vertex, and Sonoko sent spears. The creature stood no chance. It, too, retreated, and Sonoko and Sumi fell to the ground.

The jukai disappeared, and Sumi smiled at Sonoko. They had won, with almost no effort!

However, her victory was short lived. She looked down in horror, and Sonoko covered her left eye.

"Just," murmured Sumi. "Just what is this?"

"I can't see out of my right eye."

"I can't move my left leg." The two stared at each other with growing dismay. Sumi poked her leg, only to have nothing happen. Sonoko kneeled, facing the ground. Tears began to drop down, turning the ground wet and dirtying Sonoko's hands.

"No way… But…" Sumi patted Sonoko on the back, despite her own worries. Would the heroes keep fighting? "We can't stop. To protect others; isn't that why we became heroes? If I have to fight until my body is an empty shell, I'll do that. We are heroes, right, Wasshi?"

"Right," said Sumi absentmindedly, but her heart twisted. The Taisha hadn't told them. Sumi and Sonoko would have to keep fighting until they couldn't do anything except battle. The dream of what could have been had this happen. Sonoko couldn't have that happen to her. Sumi couldn't forget her dear friends.

I will definitely find a way to end this. I promise. No matter what, I'll make sure we remember each other.

In the could-have-been, Sumi said something similar to the redhead, hadn't she? In the end, she had failed. This time, though, she would make sure to protect her dearest friend until the end.