Saki was hanging laundry on the apartment roof when a delivery drone dropped out of the blue sky.

It stopped beside her and released a scratched silver package. Her name was printed on the label, but the delivery date was tomorrow.

Inside, she found a broken phone and a note in her own handwriting: Do not let this phone connect to the school network.

Saki almost laughed. Then the broken screen lit up.

A countdown showed six hours. Under it, hundreds of names began to appear. They belonged to students at her school.

Her friend Kota examined the phone that afternoon. He discovered an unfamiliar program designed to copy personal data whenever it joined a network.

“Someone sends it to school tomorrow,” he said. “Maybe future you stopped it.”

Saki remembered the technology fair. A company had offered to connect every student device to a new test network the next morning.

They took the phone to their computer teacher. At first, he suspected a prank, but the program was real and dangerously efficient. He contacted the school and canceled the test.

At midnight, the countdown reached zero. Instead of stealing data, the phone displayed a video.

Future Saki appeared on the screen. She looked exhausted but relieved.

“Good,” she said. “This time, you believed yourself.”

The image shook. Behind her, warning lights flashed across a dark city.

Saki leaned closer. “This time?”

Future Saki quickly held up another package. Its label showed next week.

“We fixed the school,” she said. “Now we need to fix everything else.”

The video ended. On the roof above Saki, a second drone was already approaching.