Hey, all! I had this random idea, and I wanted to see how it would pan out as a fanfic. Hope you enjoy it!

A Simple Thief

It was an explosion around the corner that made Deku drop his shopping bag. Iida was mid sentence, talking about a test they had coming up. All of that was forgotten as the small group ran around the support pillar and saw shattered glass littering the tile floor of the mall. Sunlight glinted off the shards. The crackling fire that had engulfed a front display case was quickly starting to spread.

A short woman bumped into Deku as she fled the fire, a fierce look in her brown eyes. She had a backpack on her shoulders, which almost knocked Midoryia down in her haste. The pit of anxiety in his chest expanded, crowding his lungs as she pushed herself off of him and continued running.

"Stop her!" the shop owner cried, coming out of the store.

"Bakugo, Midoryia, and I will go after her," Iida instructed. There was a frown on his face as he gave orders. "Todoroki, Uraraka, see what you can do about this man and the fire. And please call the authorities."

"Right."

"Let's go," Bakugo complained, taking off after the thief. "She's already got a head start!"

Deku grit his teeth and followed his classmate as he ran down the hall. With so many people around, it would be difficult to use their quirks, especially for Kacchan. Midoryia could already see the young man restraining himself. Iida couldn't use his speed either or risk running into innocent bystanders. And it would be hard to use One for All without someone getting hurt.

She was already so far ahead of them. The short woman seemed to flow between the people like the wind, easily making her way through the crowd, while Bakugo kept shouting at people to clear a path. Deku thought briefly that she must have a speed type quirk. It would make sense. Rob the store and speed away before any heroes could get there.

She turned a corner and entered an area of the mall that was under construction. Pushing aside a large tarp, she dashed into an abandoned store. The others followed just in time to see the emergency exit door closing.

Deku's lungs cried for air, and he frowned as he tried to breathe away the feeling of wrong in his chest. Why was he so anxious? Nothing was even happening. "Iida, use your quirk. Go after her."

"Right. I'll be back."

He took off after the woman, activating his power as soon as he left the building. Kacchan swore under his breath, kicking a nearby paint bucket. Midoryia put a hand over his chest, trying to slow his breathing.

"Iida will get her," he offered.

Kacchan threw him a glare and rubbed the back of his neck. "I know."

A smile pulled at his lips as he took deep breaths. "I don't think I've ever heard you express confidence in your classmates."

"Shut it."

Midoryia closed his eyes and stretched his legs. Iida would be back any second. It was just one person, and their class rep was more than capable. They'd hand her over to the authorities, who would take over the scene, and then they could all go get some food.

"Kacchan?"

"I thought I told you to shut it."

"No, look." Deku crossed the room, passing scaffolding and various painting equipment. And there, underneath a pile of loose tarps, was the woman's green backpack. The young man pulled it out and flipped it open, revealing a handful of fine jewelry along with some miscellaneous items. "It's hers."

"Yes, it is."

Izuku whipped around and saw her standing behind Kacchan, right hand raised. Before Bakugo could react, she brought her hand down and slapped his shoulder.

And Kacchan disappeared.

"Hey!" Deku yelled.

The short woman rushed him, tearing the backpack from his grasp and slapping his forearm. Izuku felt nausea roll within him. The room started spinning. He crashed to his knees, one arm wrapped around his stomach. He couldn't hear anything other than a faint buzz. Slamming his eyes shut, he tried to quell the storm within him.

The woman. Something happened when she touched him. Where was she?

"—up!"

Someone was pulling on his arm, dragging him to his feet. He felt hands on his shoulders and let out a long breath as the nausea slowly dissipated. Slowly, he opened his eyes and saw Kacchan glaring at him in a very Kacchan like way of showing concern.

"Are you alright, you idiot?"

"Yeah, I'm... where did you go? Are you okay?"

He huffed. "I'm right here. I'm fine."

"Where'd she go?"

"No idea. She ran off with her bag."

"You didn't go after her?"

"Had to make sure you didn't die. Killing you is my job."

Izuku couldn't help the grin on his face. His eyes softened as he shook his head in exasperation. "I hope Iida comes back soon. I guess I sent him on a wild goose chase."

"Listen, Deku." Bakugo crossed his arms over his chest, tilting his head. "After she touched me, I tried attacking. My quirk didn't affect her at all."

Midoryia's brow furrowed, and he looked around the room. Nothing was on fire, or singed, or even burnt. There was no evidence that he'd used his power.

"I didn't see you use it?"

Bakugo pursed his lips, rolling his eyes. "I definitely did, you idiot! You're just blind!"

The back door opened. They'd left a paint can wedged into the entryway to allow Iida to come back through the Emergency Exit once he'd caught the woman. Sunlight poured in from outside, and the young man blinked a few times as his eyes adjusted to darkness.

"Midoriya? Bakugo?"

"Over here," Deku called.

They weren't very far away, maybe a couple meters, but Izuku thought maybe he was still blinded by the sun.

He shut the door behind him and took several more steps into the room. "Guys?"

"We're right here, stupid," Bakugo barked. He ignited a few sparks on his hands to draw his attention.

Iida didn't seem to notice.

"What..."

Deku inhaled a sharp breath and walked right up to Iida, waving his hands in his face. Anxiety twisted in his chest like a snake. Alarms were going off in his mind. Something was wrong. "Hello?"

The speed hero just whipped his phone out of his back pocket and walked forward. Deku moved to the side, hearing the phone start to ring.

"Kacchan..."

"Midoryia," Iida began, talking into the phone. "I couldn't find her anywhere. I circled the mall a few times. I'm going to join Todoroki and Uraraka. Call me back when you get this message. I hope you and Bakugo have had better luck."

"What the hell."

Deku watched as Kacchan stepped right into Iida's face as he ended the call. He put his phone back in his pocket and took a step forward... Through Kacchan. The green haired boy was sure he stopped breathing. Every muscle in his body was rigid. Bakugo's mouth dropped open as he stumbled backwards.

"What the hell!"

Izuku's mind was racing. It must have been that woman's quirk. When she touched them, it must have... Bakugo whipped around and tried to catch the speed hero with his arms. They passed right through him, and Iida left through the hanging tarp.