"Satoshi," Doraemon asked cautiously, sitting on the edge of the tatami mat, "what's this rule you were talking about?"
Satoshi, arms folded, eyes calm but firm, turned to face him and Nobita.
"From today," he said, "you're not allowed to give any gadgets to Nobita… unless I give permission."
Nobita's jaw dropped. "W-What?! Why?!"
Satoshi turned to his friend and pointed at a stack of untouched notebooks on the floor. "Because if you keep using future tech as a crutch, you'll never grow. I'm not saying you can't use gadgets—but only when absolutely necessary. Understood?"
"But… but…!" Nobita pleaded, eyes almost watery. "You're being so mean! Doraemon's gadgets make life easier!"
"And life isn't supposed to be easy," Satoshi said, his voice kind yet unrelenting. "It's supposed to make you better. This is for your own good."
Before Nobita could protest again, Satoshi grabbed his hand and plopped him in front of the desk.
"Now sit. We're finishing the math homework due tomorrow."
Grumbling, Nobita picked up his pencil as Satoshi opened the textbook. Doraemon, blinking at the scene, muttered, "You're more like a big brother than a best friend."
Just then, the sliding door opened gently. Nobita's mother entered, balancing a tray of tea and freshly baked cookies.
"I thought you boys might need a break," she said kindly.
But her eyes landed on something she rarely saw—Nobita hunched over his notebook, pencil moving, mouth muttering equations with Satoshi correcting his posture.
A moment of stunned silence passed before she smiled softly. "Well… I guess I don't need to worry too much after all for Satoshi being father."
Satoshi looked up and smiled. "Thank you for the tea, Auntie."
She nodded, her expression briefly lingering on Satoshi like he was more than just a guest—perhaps a blessing to her often troublesome son.
After she left, Doraemon blinked again. "I can't believe it… Nobita's studying."
"See what a little discipline does?" Satoshi chuckled.
Then Doraemon squinted, confused. "Wait a minute. Where's Nobita's little brother?"
Nobita looked up from his book. "Huh? I don't have one."
"Huh, really?" Doraemon scratched his head. "But …but in future Nobita had …"
Satoshi leaned back against the wall and added, "His father passed away a while back. Maybe she's considering moving on… planning a second marriage."
"Wha—!" Nobita gasped, face turning bright red. "S-Satoshi, don't say weird things like that!"
Satoshi smirked. "Relax, I'm just joking. Probably."
The room filled with awkward silence, then a round of laughter—except Nobita, who had buried his face in the textbook again.
Doraemon chuckled. "You guys are something else."
They continued studying for another hour. Satoshi watched Nobita's hands fumble with grammar exercises and silently helped him correct the mistakes with patient encouragement.
But something shifted in the air. A cold stare suddenly passed across the room. Doraemon shivered slightly.
"Satoshi… why are you glaring?"
Satoshi blinked, then smiled faintly. "Oh… sorry. I was just thinking."
He stood up and stretched. "I'll be downstairs. Don't stop until you finish that essay."
As he left the room, Nobita groaned, "He's like a demon teacher…"
"Maybe a necessary one," Doraemon replied thoughtfully.
Downstairs, Nobita's mother was washing dishes, her back turned. Satoshi entered the kitchen and offered to help. She gave a tired but grateful smile. They talked—with their bodies fulfilling each other's need and spend their lovely time .
After a while , they parted ways as Nobita's mom was sweating and he also needed to check on Nobita .he thanked her for the snack and excused himself. Nobita had just finished the last question by the time he returned.
"Done?" Satoshi asked.
"Y-Yeah," Nobita huffed.
"Good. Let's check it."
They reviewed both their holiday homework together, making sure everything was neat and ready. Then Satoshi packed his things and stood up.
"I'll be heading home."
Nobita yawned. "Thanks… for the help. Even if you're strict sometimes."
Satoshi grinned. "You'll thank me later when you pass your tests without panic."
As he walked toward the gate, Doraemon floated beside him.
"You're really serious about all this, aren't you?"
"I have to be. Nobita has potential—he just doesn't see it yet. Someone has to help him see it."
Doraemon nodded thoughtfully, then looked up at the mansion Satoshi was approaching.
It loomed tall and quiet in the dusk light.
The gates opened.
His grandmother stood at the door, waiting with a warm smile and a shawl draped over her shoulders.
"Satoshi," she said gently. "Back from another busy day?"
He nodded. "Nobita's doing better, Grandma."
She brushed his hair aside with her aged hands. "You always carry the weight of others, dear. Don't forget to rest too."
He smiled, that rare smile that only surfaced at home. "I will."
That night, as the cicadas sang and the city lights flickered, Satoshi lay on his futon, staring at the ceiling.
He was making changes—small ones—but every change counted.
Doraemon had come from the future to save Nobita.
But maybe, just maybe… Satoshi had been sent by fate itself.