Work Text:
Satoru Mikami was born into a warm and loving household.
His mother doted on him endlessly, and his father was the kind of man who rarely ever raised his voice in anger.
Under normal circumstances, a child raised in that environment might have grown spoiled or self-centered.
Fortunately, Satoru had his older brother.
Kenichi Mikami excelled at nearly everything Satoru did not. He studied diligently, helped around the house without being asked, and carried himself with a quiet sense of responsibility that made even adults trust him naturally.
Whenever Satoru got carried away and threw himself into something reckless without thinking about the consequences, Kenichi would be there to scold him and drag him back to his senses.
Because of that, despite being the younger son who was endlessly spoiled by their parents, Satoru never grew into someone arrogant. If anything, he grew up feeling as though he owed Kenichi a great deal—as if his older brother had raised him almost as much as their parents had.
It began when Kenichi started dating.
At first, Satoru found it strange. His older brother had always seemed too serious to care about romance. Still, Kenichi looked genuinely happy, so Satoru accepted it easily enough.
The first girlfriend was beautiful and polite. Modest, too.
Satoru thought things would probably work out.
Then he started noticing things.
Whenever Kenichi invited Satoru to join them during outings, the girl would smile and agree without complaint.
But over time, Satoru began noticing the tiny changes in her expressions.
The slight pause before answering. The faint disappointment whenever Kenichi brought him up. The way her mood subtly worsened whenever family plans interrupted what was supposed to be time for the two of them.
At first, Satoru thought he was imagining it.
Then he realized he probably wasn’t.
He thought about refusing the invitations. Really, he did.
But every time Kenichi casually asked him to come along, Satoru found himself unable to say no. His older brother genuinely wanted him there.
And so, less than a year later, the relationship ended.
Kenichi was devastated for a while, though their parents supported him enough that he gradually recovered.
When Kenichi began dating again, Satoru decided he should probably become more independent.
He did not think the breakup had been his fault exactly, but he knew he had contributed to the problem by never refusing outright even after noticing the girl’s discomfort.
So after that, whenever Kenichi invited him somewhere, Satoru would make excuses instead.
And every time he did, he noticed the same pattern.
Initial disappointment.
Then visible relief.
Still, Kenichi never changed. He was the sort of man who valued family deeply and sincerely.
Every girlfriend he dated eventually grew dissatisfied with how naturally Kenichi included his family in his life.
One breakup became another.
Then another.
One relationship ended badly enough that the woman slapped Kenichi across the face before leaving. Kenichi brushed it off afterward and told everyone not to worry about it, but Satoru quietly carried the memory with him for a long time. The fact that his older brother had been hurt at all bothered him more than he admitted.
By the time Satoru entered high school, Kenichi introduced yet another girlfriend.
As usual, Satoru intended to stay out of the way.
At least, that had been the plan.
The girl—Emiko—was beautiful, polite, and modest, much like the others before her. But unlike the others, she was the one who invited Satoru to spend time with them first.
Not Kenichi.
Her.
She would approach him naturally, ask him questions, start conversations, and casually invite him to outings as though it were the most normal thing in the world.
At first, Satoru tried refusing with polite excuses, but Emiko refused to budge.
“You wouldn’t be a bother at all,” she insisted every single time.
And somehow, Satoru found himself unable to refuse.
One afternoon, Emiko asked him to help prepare a surprise birthday party for Kenichi.
She dragged Satoru around shopping districts while asking what kinds of gifts his brother would like.
Satoru eventually sighed and told her that Kenichi would probably be happy receiving anything from her.
But Emiko simply smiled.
“I think he’d be happier if it’s from both of us,” she said.
Satoru stared at her for a moment in genuine surprise.
Every woman Kenichi had dated until then seemed to want his brother entirely for themselves. They had all grown frustrated with how much importance he placed on family.
But Emiko was different.
When Satoru finally asked why she went so far out of her way for him when she could have spent more time alone with Kenichi instead, Emiko looked genuinely confused.
She paused to think carefully before answering.
Then, slightly embarrassed, she admitted quietly:
“Well… if things work out between me and your brother someday, then I’ll become family too, right?”
She looked at Satoru with a nervous smile.
“If I marry your brother, then maybe someday I’ll become your older sister. So I thought… it would be natural to treat you like a younger brother too.”
Satoru honestly could not remember how he responded after hearing that.
But later that night, lying awake in bed, he found himself hoping with all his heart that things would work out for Kenichi this time.
Fortunately, they did.
Around the time Satoru graduated high school, Kenichi and Emiko got married.
Watching the two of them smiling together during the ceremony, Satoru quietly thought that maybe someday, he would like to experience that kind of happiness too.
Afterward, Kenichi and Emiko moved into the Mikami household while Kenichi continued pursuing his medical career.
By the time Satoru turned twenty-two, his niece had been born.
Kenichi became increasingly busy afterward, forcing their parents and Emiko to shoulder most of the childcare.
Since Satoru still commuted from home while attending college, he naturally ended up helping whenever he could.
Then his nephew was born.
And somewhere around that time, Satoru began feeling something strange.
Kenichi’s life had stabilized.
He had a respected career as a doctor, a loving wife, children, and enough income to comfortably support the family. Their parents relied on him. Emiko relied on him. The children adored him.
And slowly, quietly, Satoru began feeling unnecessary.
It was the same unpleasant feeling he used to get whenever Kenichi’s old girlfriends looked relieved after Satoru declined invitations.
As though the world functioned more smoothly without him taking up space in it.
So eventually, Satoru decided to move to Tokyo and pursue work as a general contractor.
Kenichi and Emiko accepted the decision surprisingly easily. In fact, they encouraged it.
They felt guilty for relying on Satoru so much while he was still in college, and now that Kenichi’s career had stabilized, they wanted Satoru to enjoy his own life freely.
Their parents agreed.
Kenichi even told him not to worry about things at home anymore.
“I’ll take care of everyone here,” he said casually.
It was meant kindly.
But somehow, hearing those words only made the strange feeling inside Satoru deepen further.
So Satoru moved to Tokyo and buried the feeling somewhere deep inside himself.
He told himself it was fine.
His older brother had everything under control. Satoru was free now. Free to live as a carefree bachelor without responsibilities tying him down.
And maybe that was partly why he became the sort of adult he did.
At work, Satoru was dependable and respected. His juniors admired him, even if they occasionally found his blunt sense of humor difficult to understand. Despite his rough edges, people liked him.
His attempts at romance, however, failed three separate times.
That bruised his pride more than he liked admitting, but he eventually stopped taking it too seriously.
Instead, he buried himself in work, hobbies, and a comfortable solitary routine.
It was a simple life.
A lonely one, perhaps.
Though every so often, Kenichi would call and tell him to come visit home.
Maybe that was why, in the end, Satoru never really thought much about his own death.
When he shoved Tamura out of the path of the knife, his thoughts were strangely mundane.
His unfinished data files.
His embarrassing computer contents.
The annoyance of dying as a virgin.
But not grief.
Not really.
At that moment, all Satoru thought was that Tamura still had a fiancée waiting for him. Tamura had a future that was only beginning.
Compared to that, Satoru genuinely believed his own death would matter less.
Not because he thought his life was worthless.
But because somewhere along the way, he had quietly convinced himself that he was simply easier to lose.
So while Tamura cried desperately beside him, Satoru could only think, with detached disbelief:
Seriously… stop crying already.
It’s not that big of a deal.