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The Substitute

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Hello All! I’m back with my second Gokusen story! If you’re new, you can read Out of the Ordinary to track Shin and Yankumi through the drama and beyond, but it’s not necessary to understand this fic. I won’t say much else except to read, enjoy, and please review!


3-D thought this new teacher was weird. She looked naïve and clueless, and everyone was sure she’d faint at the sight of them, or run away at their first threats. But somehow, their rough way of speaking and tendency to fight didn’t faze her. She kept popping up unexpectedly, and making passionate speeches, and generally just weirding them all out.

But she was nothing like the substitute.

A month or two into the school year, everyone has just gotten used to how odd she was, with her mob-like phrases and the fact that she believed what they said, and even a few of them were starting to admit she wasn’t as bad as most teachers. But then one day, she didn’t show up for class.

She was normally a bit late, so they didn’t think much of it. But as the time passed, more of them started glancing at the door, wondering when she’d turn up. When the door did slide open, many turned to look, and those that didn’t were still watching from the corner of their eyes to confirm that it was Yankumi and that everything was alright.

Except it wasn’t Yankumi.

A tall, lanky man with longish hair, wearing a white shirt with a black jacket and pants walked in to 3-D’s classroom. He gave it and them a cursory glance, then closed the door, sat on the front desk, and stared fixedly at the door, ignoring them all.

The silence that had fallen lightened with curious whispers and confused looks. Reita, the unofficial leader of the class, looked up from his desk, where he had been pretending to nap (so that Yankumi wouldn’t think he was worried about her) and stared at the stranger. As much as he hated to admit it, he had almost come to rely on Yankumi’s presence and passion in fighting for them. The fact that she was gone and the stranger was here made Reita think this was somehow Mr. Jacket’s fault.

The man at the front sat up a little, as if he could sense Reita’s glare, then turned to look straight at him. When he saw Reita propping his head up on his arm, the man snorted softly, as if he was amused by something, and a ghost of a grin crossed his face before he returned to watching the door.

Reita’s fists clenched. He did not like being laughed at, especially by strangers. Scooting back his chair loudly, he started to stand with challenge in his eyes. If Mr. Jacket wanted a fight, he’d sure as hell get one.

Three things happened as Reita’s chair screeched back. An expectant silence fell over the room; the man at the front met his gaze; and his eyes flashed with their own challenge.

Reita froze. The look in the man’s eyes wasn’t amused, or superior. It was deadly serious, as if he made his living meeting challenges from people much more frightening than a high school kid. A moment passed, the man waiting to see if Reita wanted to challenge the steel in his gaze. Almost without realizing it, Reita slowly sat back down, causing a new wave of shocked whispers to echo around the room. He jerked his chin in a defiant nod, just to let Mr. Jacket know he wasn’t beaten by any means. Mr. Jacket gave his own small nod in acknowledgement, then went straight back to looking at the door.

There was hardly time for the class to wonder who the hell this stranger was and how he had gotten Reita himself to back down when the door slid open once more.

“Good morning every-” Yankumi’s overly cheerful greeting was cut short as she saw the stranger at her desk. 3-D watched the two apprehensively, waiting to see if she knew who this was.

The man’s eyes narrowed, his arms crossed, and his eyebrow lifted up in a firm glare of disapproval. As the boys stared, Yankumi paused and a look that could only be described as “Oh shit!” crossed her face.

“What are you doing here?” He asked in a deceptively calm voice.

“Um… teaching?” Yankumi answered brightly, smiling as she did when she knew she was in trouble.

“You’re supposed to be at home.” The man spoke in clipped tones, and 3-D wondered who in the world was scary enough to talk to Yankumi like that.

“But I feel fine! Really!” She responded, and from anyone else, it might have been a whine.

The eyebrow only lifted higher.

“And…” she mumbled, as if the eyebrow was a command to explain herself further. “Substitutes are hard to find.”

She didn’t say “for 3-D”, but it was clear the man heard it anyway, as he turned his scowl onto the students, who instinctively cowered.

“That aside,” he said, finally looking away from the students. “You still need to go home.”

“But if I leave, who will teach them the importance of math and studying-”

“I will.” He answered firmly. Eyes widened in shock as everyone realized he was their substitute teacher. Most subs the school convinced to teach 3-D lasted only a few hours, and it had become something like a game to see how quickly they could scare teachers off. Somehow, this guy didn’t look like he’d be that easy. The man held out his hand and beckoned to Yankumi.  “Hand over your lesson plan and go home.”

“Shin, I’m fine. I woke up feeling fit as a fiddle! Right as rain! Healthy as a horse!”

The man, who was apparently called Shin, stood and pressed his hand to her forehead. Taking a step back, he gave her another look. “You have a fever, a rather high fever, I might add, and it’s making you delusional. Now, are you walking or do you need the car?”

“I told you, I’m fine, and you don’t need to teach and I don’t need-” She was interrupted by the man taking out his phone and calling someone.

“Hello Minoru. She escaped. No, no, it’s not your fault, I saw this coming. If you could bring the car to come get her… great. Thanks.”

Yankumi looked like she was torn between pouting and pure rage. “Look, you can’t just make decisions for…” Her rant slowed as she blinked a few times, then took a staggered step sideways.

Moving faster than anyone saw, Shin leapt forward to steady her. The disapproval was gone and he instead looked extremely worried and concerned, which surprised 3-D yet again.

“ ’M fine.” She murmured into his shoulder as she half-heartedly tried to stand on her own. That was when Reita realized that this stranger might actually be right about her needing to go home.

Feeling her forehead again, Shin sighed and glanced up at the ceiling. “I really didn’t want to do this.” He grumbled softly to himself, then took hold of Yankumi’s shoulders and looked her in the eye.

“Yankumi, think of the example you’re setting.” He said, his voice suddenly falsely earnest.

Reita caught that he called her ‘Yankumi’, which he thought was odd, since it seemed like a name only students called her.

“Huh?” She blinked at him in confusion.

“If one of your students was sick, would you want him to risk his health and come to school when he was near collapsing?”

“Of course not! As their number one teacher, I’d never let them endanger themselves by ignoring… Oh.” She appeared slightly shamefaced at having out-argued herself.

“And as their number one teacher, you should set a good example for your precious students and go home.” Shin said with a remarkable amount of control.

Heaving a loud sigh, Yankumi hung her head and admitted defeat.

“Boss?” 3-D tore their eyes away from this amazing spectacle of Yankumi actually listening to someone to see a very large man poke his head through the still open door.

“Ah, Minoru.” Shin stood as the boys in the classroom once again wondered who the hell he to have a very large and scary looking man call him ‘Boss’.

“I’m so sorry, Boss, I should have kept a better eye on her…”

“It’s alright. She just needs some sleep, and is going home right now to get it.” He cast a significant look at Yankumi. “Right?”

She mumbled something that might have been about how she wasn’t five and didn’t need keepers.

“Lesson plan?” Shin ignored her dark grumblings and held out his hand. She reached into her bag and passed over the papers before she followed the large man out.


Yankumi stopped and looked back. Shin stepped towards her and pressed a gentle kiss on her forehead.

“Don’t scare me like that again.” He chided her softly as the eyes of every boy in 3-D nearly bugged out of their heads. Was this guy somehow… involved with Yankumi?

Yankumi nodded almost sheepishly, then gave him a small smile and left with Minoru.

Reita didn’t miss the tender gaze Shin gave Yankumi as she walked out. Then his eyes flashed as he turned suddenly to the class of 3-D, causing most of them to jump back in surprise (and maybe a little fear).

“All of you better remember that she was willing to endure an extremely high fever because she cares about you guys.” His glare became even sharper. “So I don’t want hear about any of you causing her trouble or hurting her feelings or any bullshit like that. Are we clear?”

Everyone gave each other unsure looks. Were they just going to sit there and take this?

“I said… Are. We. Clear?” His tone was frosty and had a very dangerous edge to it.

“Yes.” They mumbled, and some found themselves adding ‘Sir’ without realizing it.

“Good.” His voice was back to normal. “Now, if you take out your books and turn to chapter three…” Shin faced the board and picked up a piece of chalk. When he didn’t hear any books being unearthed, he paused a moment, then flashed a look over his shoulder. Suddenly, math books started appearing out of nowhere, many dusty with disuse.

Thus passed the strangest, quietest, and most focused math lesson 3-D had ever had.

When the bell rang, Shin gathered the papers, told them to study the next chapter, then left. As soon as the door shut behind him, the class burst into conversation.

“Who was he?”

“How did he know Yankumi?”

“Did you see the way he looked at her?”

“Did you hear how he talked to her?”

“Dude, Reita backed down!”

“No wonder! I nearly pissed my pants when he glared at us.”

“I think he must be a bodyguard or something.”

“Why would Yankumi have a bodyguard?”

Reita sat silent as his classmates buzzed around him. He didn’t know what to make of this substitute, which unsettled him. He liked having control, having a sense of who and what people were. But Shin Whatever-His-Name-Was did not fit into any of the categories he knew, and he wasn’t sure what to do about it.

Yankumi returned the following Monday as if nothing out of the ordinary had happened.

“Good morning everyone!” She declared happily as she came through the door.

But instead of the class ignoring her, or giving her mumbled greetings, everyone started shouting things at her.

“Yankumi! You’re alive!”

“We thought you got kidnapped!”

“Thank God it’s not that scary guy!”

“How do you know him?”

“Are you in trouble with a gang or something?”

Paying absolutely no attention to what was said, Yankumi heard only the tone of relief all her students had.

“Aw, you missed your favorite teacher! I missed all of you too, but, no need to worry, I will be here for you always, to the very end! And we shall never perish as long as we come together and strive for-”

“We didn’t miss you.” Reita interrupted, deflating her energy. “We just thought that guy was weird.”

“Oh,” Yankumi said as his classmates gave him apprehensive looks. The scary guy had said to not hurt her feelings, after all.

But, with her usual enthusiasm, she quickly perked up. “Well, let’s see what you learned on Friday! Everyone open your books and-”

“Who was he, anyway?” Reita asked with a raised eyebrow. This time, the whole class leaned toward Yankumi, who froze while facing the chalkboard.

“He’s my… well, it depends on… I mean, I know him from…” Reaching a roadblock, she flashed a large smile and said extra loudly, “Let’s move on!”

And that was all they learned about the mysterious substitute for a while.

Until he came to rescue them.