Author's Note: While Aizawa is easily my favorite character in the MHA-verse, Iida is probably my favorite among the students... and both are in no small part because of the talent of their respective voice actors in the English dub (Chris Wehkamp and J Michael Tatum). So, as per usual, my muse started yelling at me to do a story about the two of them. This was the result. Enjoy.

I SHOULD HAVE KNOWN BETTER

"That's it for today," Shota Aizawa said, tossing the chalk he was holding onto the ledge of the blackboard. "I'll be expecting your reports on your internship activities on my desk by the end of this week - be sure to include both the good AND the bad. Dismissed."

As Class 1-A began their mad dash toward the door, Aizawa's voice cut across the babble once again.

"Iida... I'd like a word with you."

Tenya Iida halted halfway out of his chair, his eyes wide behind his spectacles and his face pale. Behind him, Ochako Uraraka let out a soft "uh-oh" before leaning forward to give Iida an encouraging pat on the shoulder. "I'm sure it's nothing, Tenya," she said quietly.

Izuku Midoriya also gave Iida a tentative smile. "Yeah, it's probably just class rep stuff. And better you than me, actually! Uraraka and I will wait for you if you want so we can all head to the station together."

Iida swallowed hard, then shook his head. "No. I appreciate the offer, but I don't know how long this will take, and I don't care for making you both wait for me. I'll see you both tomorrow, if I don't catch up with you before you get to the station."

While the rest of class 1-A headed out, most with sympathetic, curious, or doubtful looks in Iida's direction, Iida finished putting away his books, stood up, and straightened his clothes before advancing toward Aizawa, who was leaning against the doorframe.

"Come with me," Aizawa said, and with his sleeping bag over one shoulder, he led Iida down the halls to one of the teachers' lounges. He waved Iida to a seat and tossed his sleeping bag over the back of the couch before sitting down as well.

Iida was doing his best not to fidget or flinch under his homeroom teacher's implacable stare, but it was difficult, given Aizawa's uncanny talent for seeming to stare right through a person.

Just when Iida thought he would crack from the strain of the silence, Aizawa finally spoke.

"I'm sorry about Tensei."

"Oh. Thank you, sir."

"How is he doing? Any progress with his recovery?"

Iida let out a low sigh. "It's... it's slow-going, and frustrating, too. I mean, I'm grateful that he's even alive, considering what Stain could have done, but still..." He growled and clenched his hands into fists. "He may never walk again, and even if he does... Ingenium is gone."

For a moment, Aizawa just stared at his student, then he closed his eyes and rested his head on the back of the couch.

"I also heard about your behaviour in Hosu."

At that, Iida froze, the building anger and frustration and regret about his brother stifled in an instant. But before he could speak, Aizawa went on.

"It was obvious in retrospect, really. You're one of UA's top students, you placed highly in the sports festival, which meant you had plenty of offers for more prestigious and frankly more appropriate internships, given your skills and your goals. And yet you took a fairly low-level one, with a much less well-known hero, in the city where your elder brother just happened to be injured in the line of duty. Not because you wanted to take up his slack, not because it was closer to the hospital where he's convalescing... but because it suited your need for revenge."

Hearing it spelled out like that, Iida squirmed in his seat in an agony of embarrassment.

"Sir, I-"

"I'm not finished."

Iida immediately clapped one hand over his mouth.

"You should know better than that, Iida. After at least two months here at UA, not to mention your family's long-standing tradition of heroism, you should have known that revenge is not heroic. It's a hero's job to protect, not to punish. That's what the legal system is for. Heroes exist to facilitate that system, not replace it. It's a hero's job to save lives."

"Use your Quirk to save others - be a real hero."

"You might also want to think about how many people you hurt. And I don't just mean Midoriya and Todoroki. You nearly cost Native his life by prioritizing your revenge over his safety. You let Manual down by disrespecting his faith in you and his internship offer. Never mind how many pro heroes were possibly counting on you as Manual's backup during that fiasco. And with your speed, who knows how many civilians you might have been able to get to safety while the pros were fighting those Nomu?"

Iida stared down at the floor, his shoulders slumped and his head bowed.

"After all, that's what being a hero is all about - ensuring the safety of others..."

Then Aizawa let out a sigh and opened his eyes.

"But... I suppose it's my fault as well, though. The moment I saw your internship form, I should have realized what you were planning to do. And I should have known better than to let you go through with it."

That hurt Iida almost as much as the Hero Killer's blades. God only knew that he didn't always agree with his teacher, or condone his methods when it came to his students, but Iida never once doubted that Aizawa always had his students' best interests at heart. And to hear that his teacher was to some degree blaming himself for his mistakes...

He squeezed his eyes shut to hold back unexpected tears. "Mister Aizawa, please, you... you shouldn't blame yourself for my immature and reckless behaviour." His voice was thick with emotion.

"I even briefly wondered about it at the time," Aizawa admitted, finally lifting his head to look directly at Iida. "But I genuinely believed that you were smarter than that. You're always the one harping on others about how heroes are supposed to conduct themselves, holding everyone to the same standard that you normally hold yourself to. So I figured that maybe you just needed to see for yourself what kind of world your brother was fighting in, and fighting for."

Aizawa tiredly rubbed his eyes, then very quietly rasped, "But I guess even teachers don't know everything. I'm a great one for logical thinking, but sometimes I forget that you're still just a child of fifteen. I'm sorry, Iida. As your teacher, I let you down."

Tears slowly slid down Iida's cheeks, and he couldn't make himself look at Aizawa anymore. He looked down at his hands... at his injured left hand.

"Until I'm able to call myself a real hero, I'll leave my left hand as it is."

"N-no," he whispered at last. "It's not... it's not your fault. You're right. I should have known better. And I... I am still a child. I didn't... I didn't want to accept help. Not even from my... from my friends."

Then he abruptly turned to look Aizawa in the eyes and said fiercely, "But I won't make that mistake again, sir. I promise. And... and if you'll forgive me for saying so, I know you won't, either."

The corner of Aizawa's mouth turned up slightly, and his eyes narrowed in quiet approval. "Good enough for me. Now get out of here. At your best speed, you should be able to catch up to Uraraka and Midoriya before they reach the station. Assuming I haven't misjudged you, of course."

Iida rose to his feet and bowed to Aizawa, then he smiled tightly at his teacher.

"You haven't, sir. And thank you."

Aizawa nodded, and then stretched out on the couch, closing his eyes once more with a relieved sigh, while Iida bolted from the room, down the hall, and out into the sunshine in pursuit of his friends.