tw: mentions of injury (chemical burn)
The pov changes a bit

You hissed in pain, dropping the vial, luckily over the sink. The parts of glass that were left shattered, but quickly started burning once exposed to the chemicals.

You swore a few times under your breath as you turned the facet on to flush the chemicals off your hand as fast as possible.

You'd been helping Bruce with an experiment with a couple of months now. Tony insisted on not telling you what it was for, but from what you understood, some new kind of element was found, and Tony and Bruce were trying to figure out what it works best with. And apparently under the right conditions it could...burn glass....because we needed more elements that could burn glass.

You bit your lip.

The spill still burned, but it looked like it didn't do too much damage to your skin.

"JARVIS, could you get Bruce?"

"It's already done, sir." The AI responded.

"Thanks." You exhaled, looking around for something to clean the burn up with. Not that you knew the first thing about treating burns, but there had to be some kind of ointment or something, right?

Moments later, Bruce rushed into the lab.

"Y/n, JARVIS said you were hurt."

"Burned, sir." The AI spoke.

Bruce was already at your side, you were still standing at the sink. He grabbed your wrist gently and blinked at you.

"You didn't wear any gloves?"

"I-uh..."

"Y/n, if you're going to be in here with me, you're going to have to use the right equipment. I can't have you getting hurt."

"Sorry."

He sighed. "No, I'm sorry. I'm not mad at you. It's not a bad burn, here."

Bruce got a paper towel, and dampened it with cold water before wrapping it gently around your hand.

"This should help with the pain. Petroleum jelly should also help it heal." He murmured.

"Thanks." You said, the burn starting to feel slightly better.

"Why weren't you wearing gloves? You know that's one of the first things I taught you."

"You said it was harmless."

"I thought it was. You should still wear gloves."

You only nodded, and there was a silence between you two, and a small blush grew in Bruce's cheeks as the took the opportunity to take in your features.

"Well, I'm going to go. Probably shouldn't be in the lab anymore today." You chuckle.

"Right." Bruce says, snapping out of his trance. "Um, keep a cold wash cloth on that if it starts to hurt. And um petroleum jelly will help it heal."

"Right., thanks." You say, leaving, carefully keeping your hand near you so that it doesn't bump into anything.

Once you were gone, Bruce sighed, putting his face in his hands, and running his fingers through his hair.

The two of you had been friends for a while, but he'd grown to like you...really like you. He freaked out when he heard you had been injured.

He shook his head, trying to concentrate on the element. He thought it was completely safe, it shouldn't have hurt y/n, or anyone for that matter.

He frowned, and got to work.

*time skip

It was much later when Bruce came to check up on you.

You were laying bed, half asleep when you heard your door open. You sat up half heartedly and blinked to see Bruce.

"Sorry, I was just checking to make sure you were okay."

"Oh, yeah. It's fine. Hasn't gotten much worse."

"That's good...goodnight y/n." Bruce whispered, turning to leave.

"Wait."

He turned back. "What?"

"Stay." You said sleepily.

"Oh, uh...okay...sure..."

Bruce closed the door, and made his way over to the bed, carefully getting in.

The two of you did a fair amount of shifting around, before you finally got comfortable.

Once you were asleep, Bruce looked at you and smiled. He carefully brushed some of your hair away from your forehead and whispered "I love you."

"I know, that's why I told you to stay."

Bruce shot up in surprise.

"Oh my god, I'm so sorry, I thought you were asleep."

"Because that doesn't sound creepy. No, stay here." You wrapped an arm around his waist before he could get up, and pulled him back in next to you, up against your chest this time. "It's okay, I love you too." You said, kissing his forehead.

Bruce lay there for a while, his heart pounding while you rubbed his back and his hair to try to get him to calm down.

After a while, he did, and fell asleep peacefully snuggled up against your chest.