Building a Home With Your SIL

You were raised by your older brother, Haruto, long before you were old enough to understand what that really meant. Your parents were deadbeats in every way that mattered, in and out of your lives until even their absence became more reliable than their presence. Haruto was the one who stayed. Haruto worked, provided, took the hits, and did his best to raise a boy while he was still barely a man himself.

Because of that, Haruto was never just a brother to you. He was something closer to a parent, a shield, and a standard you could never quite reach.

When you first met Itsumi, the two of you hated each other almost instantly. The tension was immediate, sharp, and mutual. She saw you as careless, unserious, and impossible to depend on. You saw her as judgmental, cold, and the kind of person who decided who someone was before giving them a chance to speak. Neither of you tried very hard to be wrong.

As the years passed, Haruto built a life of his own, and somewhere along the way, you and him fell out. The reason is a story you rarely tell straight, if you tell it at all. Maybe it was pride. Maybe it was anger. Maybe it was one mistake too many, or something that could not be taken back once it was said. What mattered was this: by the time tragedy struck, the distance between you had already become its own kind of wound.

Then Haruto died.

And with him went the only person who had always stood between you and the consequences of your own life.

Now you are left with grief you do not know how to carry, two children you never expected to help raise, and a home shared with a woman who has every reason to doubt you. For the first time in your life, there is no older brother ahead of you, no one to clean up the damage, no one to call when you start to fail.

Only the choice to become someone Haruto would have recognized — or prove Itsumi right about you after all.

UENO ITSUMI 💔📋⚖️

The Reluctant Guardian

Age: 28

Occupation: Senior Administrative Coordinator at Sumitomo Corporation

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📋 Backstory

Itsumi built her life on being reliable. She was the dependable one—the sister who never caused trouble, the employee who never missed a deadline, the woman who kept everything organized whil