(Prologue)
There is a saying that life is a battle.
It is a battle that no one has truly come to understand.
One can say that living is the hardest battle a person will ever experience.
Very few will claim that it is easily fought.
The one thing that many people have in common with each other is that they are alive.
And because they are alive, one could also believe that every living person is fighting their own battle.
If they are lucky, another person may offer a helping hand.
For the not so lucky, they will have to fight alone.
Right now, at this moment, Shinji Itsuka could not help but wonder if he was alone in his own battle.
"Onii-chan wake up, you're gonna be late!"
Playfully jumping and dancing on her brother, Sawa Itsuka takes the initiative in the battle of waking up on a Sunday morning, her long brown hair swaying as she twirled and hopped.
It was a strategy that one of her aunts had told her about.
"Mmmm, Sawa, it's Sunday. Let me sleep in."
Though the younger sister had taken a preemptive strike, she had neglected to lower Shinji's defenses.
What separated the sleepyhead from complete annihilation was the blanket that he had pulled over his head.
However the little girl had already devised a counter to her older brother's shield.
If Sawa could not lower Shinji's defenses, she would instead make him come out on his own.
"Yeah but mama has work today! You told her you'd help out at the clinic!"
Even on a Sunday, there were still battles to be fought.
While some may be resting, the world continues to turn for most.
There are times when adults must continue to fight, even when their children are allowed a moment of peace.
"Ah! That's right!"
Realizing that he had forgotten something important, Shinji abruptly rises from his slumber, causing Sawa to lose balance and fall off the bed.
A yelp could be heard as she fell, followed by a violent shaking throughout the house.
"Ow...Onii-chan, you jerk!"
"S-Sorry Sawa, I'll make it up to you okay?"
Shinji puts his hands together as if he was doing a prayer, hoping that his little sister still had mercy in her.
"I'll forgive you just this once."
Sawa stands up rubbing her bottom, and immediately after points towards Shinji.
To be more specific, she was pointing past Shinji and at the person who was lying next to him.
"But Onee-chan, you've got to get up too!"
Unaware that someone had been sleeping next to him this entire time, Shinji looks beside him.
There he finds a girl with long pale blue hair, her back facing him.
She was close to his age.
And she was also his older sister.
Recognizing that Sawa's shouting was directed towards her, Mio Itsuka droopily opens her eyes and slowly turns along the bed.
"Mmmm, Sawa, can you let Onee-chan sleep for a little longer?"
Despite looking sleepy, Mio's eyes revealed the beautiful color that was the same as her hair's.
Just from looking at her, Shinji's heart had skipped a beat.
"You snuck into my bed again!?"
He recoils from finding his other sister in his room.
Mio on the other hand only stretches, still lying down, before turning to smile at Shinji.
"Morning Shin. Do you have a problem sleeping in the same bed as your sister?"
"I don't even know where to start with that!"
It had not been the first time.
But even after all the times they had spent sleeping together, Shinji could never get used to them.
And the reason was not a very complicated one, for Shinji had already known.
He was in love.
"You have your own room!"
Mio giggles.
"Then should we sleep there?"
"No, that's not what I meant and you know it!"
Understanding that Mio was teasing him for her own amusement, Shinji throws off his blanket and hops out of his bed.
"I don't have time for this, I'm going to see mom."
He hurriedly approaches the closet to prepare his change of clothes, continuing to speak to his sister with his back facing her.
"Stay here if you want."
Seeing her brother on the move, Mio begins to raise her own body out of bed.
"It's Sunday, so I doubt she's that busy. She'll understand if you're a little late, won't she?"
Shinji freezes for a moment.
Because he had grown up with Mio, he knew the ulterior motive behind what Mio had asked.
He turns his head to look behind him - to look at Mio.
"You really don't want me to go, do you?"
Mio shakes her head.
"That's not it, I'd just rather have you be with me."
Sawa had remained silent.
She had rested her arms on Shinji's bed, watching the two of them with a grin on her face.
There was a hint of sadness in Mio's voice.
That sadness had formed a pause between the dialogue of Sawa's siblings.
Shinji continued to look behind him and towards Mio.
Mio continued to look towards Shinji, most of her face expressionless.
The only exception was her eyes which showed a sense of longing.
Neither of them said a word to each other for a while.
Not until Shinji gave an exhausted sigh.
"...Want to come with me then?"
Mio gives a small nod.
"Yeah."
Shinji turns back to his closet and continues to pick out his clothes.
"...You didn't even have to ask."
His answer makes Mio give a small smile.
"Thanks, Shin."
"I want to go too!"
Sawa finally speaks, raising a hand as if trying to get a teacher's attention in class.
"Then you two get changed. I'll go make breakfast."
Shinji had finished choosing his clothes and was facing the two sisters on his bed again.
"But Mio..."
Mio, still sitting on Shinji's bed, tilts her head quizzically, waiting for her brother's next words.
"Change into your own clothes!"
Shinji's yelling could be heard throughout the house.
Mio had not understood that borrowing her brother's button-up shirt was not something a sister did to her brother.
So all she could do was tilt her head the other way before her brother threw both of his sisters out into the hallway with absurd yet gentle strength.
Surprised, Mio and Sawa look at each other.
Neither of them could hold back their smile and giggle, thinking about how fun today was going to be with their brother.
"Morning, sleepyhead."
A man making breakfast for his children calls out towards the living room without looking, his attention not leaving the eggs on the frying pan.
The father had heard footsteps approaching, but not until after the giant fuss that occurred upstairs moments ago.
"Morning dad."
Shinji approaches the kitchen and yawns after greeting his father.
"Breakfast is almost done, so relax."
Without saying a word, the son of Shido Itsuka obediently takes a seat at the dining table.
"Did you send Sawa to my room?"
Not hesitating to ask, Shinji asks about his father's intentions.
"Well yeah, you weren't going to wake up any time soon."
Shido knew his son too well, as he was very much like him.
There had been days when his sister would go to wake him up in the exact same way.
It would be too embarrassing to admit that she would still do it to him now and then at her current age, though nowadays she would have others join in and make it worse for him.
"Did Mio go into your room too?"
Seeing that breakfast was nearly ready, Shido finally looks behind him to see his son resting an elbow on the table and supporting his head.
"Yeah, clingy and a brocon as usual."
"That's just how much she loves you."
Deep down Shido was not actually sure if Shinji had been joking or not.
However Shido himself had gone through having to deal with the romantic love that one of his sisters had for him, though the circumstances were a little different.
In the end Shido's feelings had ended up elsewhere, but no matter how alike he and Shinji were, it was not certain that things would turn out the same way for the son and older daughter.
Now that times had changed, it was certainly hard to tell how the two of them would end up.
But whatever was going to happen, the parents had already decided long ago to support the siblings in the best way that they can.
"Thanks for understanding dad."
"That was fast!"
Mio had immediately entered the living room having heard the last thing her father said.
She had already changed into her own clothes, much to Shinji's surprise.
"You really hate being away from your brother, don't you?"
Shido himself could only ask in disbelief.
There were times when Mio's love for Shinji surprised even the parents.
"Aren't you the same way with mom?"
"Can't argue with that."
Shido shrugs.
His disbelief had already gone and was replaced with feelings of surrender.
"No, you can totally argue with that, don't just give up."
The disbelief had been inherited by Shinji.
"Once again, I told your mom that you'd be late, so there's no need to hurry."
Shido had already prepared some eggs on toast and placed them on the dining table.
"Thanks. Then let's eat."
Shinji brings the slice of toast to his mouth ready to bite into it, but he remembers to ask Mio something first at the last minute.
"Wait, Mio, did you just leave Sawa by herself?"
"She said she could get ready by herself, and I trust her."
Mio, who had already began eating her breakfast, answered nonchalantly.
"They grow up so fast."
Shido was leaning against the counter, having already eaten his breakfast.
"One minute they're just babies and the next minute they're in grade school and high school."
The proud father folds his arms and gives a confident nod.
"...if only your grandparents could see you."
Shinji and Mio look at each other for a moment before looking back at their father who had a sad smile on his face.
The two of them had only heard stories about their grandparents.
Apparently neither of those grandparents were alive anymore.
But like every grandparent they had contributed much to the lives of their grandchildren.
"Is it true that you named us after them?"
"Yeah. Did your mom tell you?"
"No, Mana-san did."
"I see."
There were moments when Shido would talk about them and make the same sad smile.
And the curiosity of the children, Sawa included, would grow.
That's why Mio couldn't help but ask another question.
One that was a little different from the previous one.
"But then who is Sawa named after?"
"Sawa was...an old friend of your mom's."
Sawa Yamauchi was no longer alive either.
None of the three children knew what had really happened to their mother's friend.
The times that they had asked, she only promised that she would tell them someday later.
"Come to think of it, weren't you the one who named Aunt Tohka too?"
"Y-Yeah..."
A bead of sweat poured down from Shido's face.
"But she's our aunt. Don't you usually come up with names for your own kids?"
Shinji had been wondering for a while about the strange girl named Tohka Yatogami.
From what he had heard so far, it was starting to sound as if she appeared out of thin air one day.
"Our family history is a bit...complicated."
It was difficult to conceal the entire truth about the Itsuka family.
But at the same time no one wanted to lie to Shinji and his sisters.
Thus it was agreed upon that the truth would be leaked out little by little.
And even though Shinji and Mio were in their second year of high school now, the questions never stopped coming.
"But Tohka is definitely family. That much you can be certain of."
Even if she wasn't the mother, Shido still loved her very much, and the real mother had understood that perfectly.
"Well yeah, you didn't need to remind us."
"Good to hear."
Shinji's confident answer causes Shido to smile again, but this time it was from the pride in his son rather than the emptiness left by the grandparents.
"Speaking of your Aunt Tohka, you're seeing her after you visit your mom, right?"
"Yeah. Want us to tell her you said hi?"
"Well that'd be nice too, but I was hoping you could drop off some food for her."
Shido brought out a bag of mostly kinako bread.
Looking at the bag reminded Shido that Tohka had never outgrown her love for food, even after all these years.
That, however, was never a bad thing in Shido's eyes.
"Yeah, you can leave it to us...ah, hey, Mio! Did you take my other toast!?"
Mio glances at Shinji before looking the other way, continuing to eat a part of Shinji's breakfast.
"You could've just asked..."
Their aunt Tohka wasn't the only one who had fallen in love with food.
Though just like Tohka, food was not the thing that Mio loved most.
"Okay papa, we're off!"
Sawa had struggled a little to get ready for the day, but in order to prove Mio that she was capable of taking care of herself, she had persevered.
Since the parents seemed to have expected their kids being late, Sawa was also able to take her time eating breakfast.
"Sawa, look after your brother and sister for me, okay?"
"Hehe, leave it to me!"
With her father waving by the front door, the three siblings leave the house.
The moment they were out of sight, Shido felt his phone vibrate in his pocket.
"Hello?...Oh, yeah, they just took off."
The voice on the other end of the phone call belonged to someone who Shinji and the others knew quite well.
But it was also a voice that Shido knew even better.
Despite having heard the voice for most of his life, not once had he grown tired of it.
"Yeah, you already know. I've got work today too, so I'll meet up with you later."
Now that the both of them had become fully grown adults and parents, life was much harder to do what they always did back when they were young.
"...You're a veterinarian, why do we need to go to a pet shop after you get out of work?"
Although their lives had changed, the couple themselves have not.
"...No, I don't want to go to that lingerie shop, we've been there so many times now. You've got plenty."
And so their feelings for each other have also remained unchanged.
"...The kids will be home tonight. We can't do that."
Or rather, they continued to grow.
"Good, a dinner date's good enough. Don't forget to thank Nia for paying for us."
Laughter could be heard from the other side of the phone call.
Followed by some heartwarming words.
"I love you too. Later."
"I told him over and over that he didn't have to come and help me today."
Letting out her thoughts and finishing them with a sigh, Shido Itsuka's wife puts away her phone after ending a passionate call with her husband.
She walks out of the break room and makes her way to an exam room a few doors over to continue her work.
"Pardon me...Oh, hello there."
Shinji Itsuka's mother is greeted with a cheerful dog walking up close and wagging its tail.
"There there, good boy."
The mother had been a good parent, but one could argue that she was just as good at taking care of animals.
"Hello, doctor."
The dog's owner was an elderly looking lady who had been keeping it company.
"I'm terribly sorry for the wait, today has been busier than usual."
The veterinarian stands up after petting the dog, diverting her attention to the owner.
"Oh, you don't have to worry about that. I didn't wait very long at all. Besides, he seems to be doing much better already since the last visit."
"Yes, you're right about that."
The dog's current behavior was already a sign of good health in comparison to the earlier appointments.
Its happiness was noticeable to the point that the doctor couldn't help but crouch down and pet it again.
She had always been more of a cat person, but regardless it took everything she had not to take it outside and play.
"Umm, I'm terribly sorry, but I believe my age might be catching up to me."
Containing her urge to spoil the dog, the happy doctor looks up to see the elderly lady looking a little confounded.
"I've taken him to this clinic many times already, but I still haven't remembered your name."
Hearing the lady confess her problems, the proud mother of three smiles.
"That's quite alright."
She stands up again to introduce herself, not bothered in the slightest over the visitor's concern.
"It's nice to see you again."
The young woman's voice was gentle, her words polite.
"My name is Itsuka."
Even though she was working on a Sunday, she must have been in a good mood.
Because her smile never went away for the rest of the day.
"Kurumi Itsuka."