Just as Nobita stewed in his misery, his eyes landed on Lin Yu, engrossed in drawing. Suddenly, a desperate, yet, in his mind, ingenious, idea sparked.
...
The melodious chimes of the school bell echoed, signaling the end of another day's lessons.
Lin Yu stretched lazily. He'd spent the entire day drawing, feeling a bit like he was cramming homework on the last day of summer vacation. His hand throbbed with a dull ache.
'Looks like I'll need to incorporate some regular exercise,' he mused. 'Wouldn't do to develop occupational hazards at such a young age.' He thought this while packing his schoolbag.
"Lin Yu," Shizuka, who sat in front of him, turned around, her voice soft. "Do you have a moment later?"
"What's up?"
"Today's homework from the teacher seems a bit tricky," she explained, a slight frown on her face. "There are a few parts I don't quite get. Could I possibly ask you to help me with them, Lin Yu?"
Lin Yu blinked, a blank expression crossing his face as he tried to recall the day's assignments. His mind drew a complete blank; he'd been so engrossed in drawing that homework hadn't even registered.
Seeing his thoughtful pause, Shizuka mistook it for hesitation. She quickly opened her notebook and held it out for him to see. "See? These problems," she said, pointing. "They feel really difficult. I haven't got a clue where to even start."
Lin Yu glanced at the problems and breathed a small sigh of relief. Though he had an adult mind, if they had been the kind of ridiculously complex 'Elementary Olympiad Math' problems from his previous world, he genuinely wouldn't have been sure. After all, it had been years since he'd left school; most of that knowledge had long since been returned to his teachers. Fortunately, Japanese elementary education wasn't quite as outrageously difficult as in his past life.
"Mm, no problem," he said. "Actually, this problem..." It was still early, and helping Shizuka solve them wouldn't take much time.
"Hey, Lin Yu!" Just then, Nobita seemed to pop out of nowhere, slapping Lin Yu on the back a bit too enthusiastically.
"Huh? Nobita..." Lin Yu began to greet him, but then his eyes flickered, and he tilted his head, a slightly puzzled expression on his face.
"Hmph! Nobita, I'm not speaking to you!" Shizuka began, still miffed from earlier. "If you don't apologize to me, I'll..."
"Hey, Nobita!" Gian's voice boomed, cutting Shizuka off. He and Suneo had materialized, flanking the now-perplexed Lin Yu. "You were pretty cocky this morning. Did you forget what I told you?"
Despite the sudden turn of events and Gian's menacing presence, Lin Yu's expression remained remarkably calm. Instead, he subtly tilted his head, his peripheral vision catching a glimpse of something on his own back. A small sticker. And on it, the characters for 'Nobi Nobita.'
Understanding dawned instantly. The Substitute Sticker.
As a devoted Doraemon fan from his past life, Lin Yu had a vague recollection of this somewhat obscure gadget. The Substitute Sticker, if he remembered correctly, worked by writing the name of a person or object on it and then affixing it to something else. This would alter how others perceived that 'something else.' However, the change was purely superficial. For instance, if you stuck a sticker with 'Ultraman' written on it onto yourself, people would perceive you as Ultraman, but your memories wouldn't change, nor would you suddenly possess Ultraman's powers. If you wrote 'mailbox' or 'tree,' people might perceive you as such, perhaps even making you feel rooted to the spot, but you wouldn't actually gain the properties of a mailbox or a tree.
Therefore, even though he now bore a sticker identifying him as Nobi Nobita, his own thought processes remained perfectly normal. The sticker on his back was proof enough that he was under the effect of a gadget. And there was only one person who would pull such a stunt...
A wry smile touched Lin Yu's lips. That mischievous Nobita! Always stirring up trouble, and now, having made a mess, he was trying to get Lin Yu to take the fall.
Looking at Gian and Suneo, who were now cracking their knuckles expectantly, Lin Yu let out a small, knowing laugh.
"I'm sorry," Lin Yu said, his voice a perfect imitation of a repentant Nobita. "I was really out of line this morning. I hope you can forgive me. As an apology, how about I give you some of my treasured manga?"
Gian and Suneo exchanged bewildered glances. They'd come to teach Nobita a lesson, but truth be told, if it hadn't been for Nobita's outrageous attitude that morning, this probably wouldn't have escalated. They'd known each other since kindergarten, and while they bullied Nobita, it was usually (in their minds) for a reason. Now, faced with 'Nobita's' earnest apology and an offer of manga, they were completely thrown. The contrast to his usual behavior was jarring.
"For real? Did I hear that right?" Gian asked, still suspicious, though his eyes lit up at the mention of manga. He flexed his fist. "If you're trying to trick me, you'll regret it!" Free manga, after all, was an offer no kid could easily refuse.
"Of course, I wouldn't trick you," Lin Yu ("Nobita") replied smoothly. "You can come home with me later to get them."
Lin Yu then turned to Shizuka, his tone equally contrite. "Shizuka, I'm really sorry about this morning. That was wrong of me. Please forgive me. Why don't you come over to my place with Gian and Suneo too? We can all do our homework together."
"Well... since you've apologized so sincerely," Shizuka relented, a small smile appearing, "I forgive you. But please, don't ever do something like that again."
With Lin Yu's smooth apologies, the aggressive tension that had filled the air around the trio instantly dissipated.
Only Nobita, who had been eagerly anticipating the 'show,' stood to the side, a growing sense of unease creeping over him. Something felt very, very wrong. This unease turned to outright panic when he heard Lin Yu offer his manga as compensation.
"No, no!" he yelped, rushing forward. "That's all my manga!"
Gian turned, giving the real Nobita a puzzled look. "Who's this kid?" he asked, scratching his head. "Has he been standing here this whole time?"
"Don't know him," Suneo shrugged. Shizuka also shook her head, looking equally confused.
Seeing their confusion, Gian rolled up his sleeves and scowled at the real Nobita. "That's Nobita's manga," he stated firmly, jerking a thumb towards Lin Yu. "And Nobita wants to give it to us. What's it got to do with you?"
"I..." Nobita stammered, utterly speechless.
He didn't dare rip the sticker off Lin Yu now. If he did, his whole prank would be exposed. Not only would he face a guaranteed thrashing from Gian and Suneo, but the deliberate deception would make everyone even angrier.