Prompt: Fitzsimmons + "I bet I can make you scream my name"

"It's on."

Jemma and Fitz stood staring at each other as if a Wild Western showdown were about to go down. Fitz's lips twitched upwards.

"What do I get if I win?" Jemma inquired. Fitz licked his lips in deep thought. Jemma chomped down on her bottom lip. Why did he have to be one of those people who had the ability to be effortlessly hot?

"The loser has to do whatever the other person says for a whole day." Jemma's eyebrows shot up.

"The whole day? Wouldn't that interfere with our work?"

"No! We're both reasonable adults. We have the ability to control ourselves and only make reasonable demands." Upon seeing Jemma's hesitation, Fitz leaned back smugly. "Unless, of course, you're scared to lose."

That struck a nerve, and Fitz knew it. He knew that she was the bravest person in perhaps the entire team, and he knew that she knew it. After all, it was Jemma who had survived 4 months on that planet, enduring things the others couldn't even begin to understand. No, people would have to be absolute fools to call her scared.

"Deal." Jemma held out her hand, which Fitz shook. And so the bet was in motion.

This was going to be fun.

Over the next few days, the two tried many different ways to make the other scream their name. Everything from really good sex to irritating the heck out each other was used, but the two remained as stubborn as ever. Jemma had even gone so far as to put Fitz's favourite sandwich next to an incredibly smelly alien substance they were working on.

He'd nearly snapped. Multiple times. He almost hated Jemma for being stronger and more put together than him; that her temper was much more under control. It sucked that it only made him angrier and more determined to beat her.

The rest of the team had caught wind, and were enjoying the competition immensely. They'd even found out that Daisy had started a pool, which only fueled their determination.

In every spare moment he had, Fitz was researching ways to make people scream, but all his attempts were futile. It was increasingly frustrating. Then, one day in early October, he came across a random blog page, talking about how much the writer liked Halloween. He had no idea how he had found it, but he did know that he'd just hit the jackpot.

Jemma would be screaming his name in no time. He just had to hold out for the 31st.

As the day rapidly approached, Fitz changed his research time to creating time. He was going to give Jemma the scare of her life. He went out, collecting the spookiest things he could find, and was even able to sweet-talk his way into borrowing some of his friend's spooky things. Soon, he had a plan set out. He just needed a couple of hours to set it all up.

Fortunately for him, Jemma was out for most of the afternoon on a mission, and wouldn't be back until after the sun had set. Perfect. That gave him plenty of time. As he set up, he asked each of his friends not to touch anything as he encountered them. They agreed with smirks and faces full of glee.

The time soon came, and Fitz grinned sinisterly from his hiding place in the shadows as Jemma boarded the plane, quite clearly tired from her mission. The look of exhaustion on her face was almost enough to make him feel bad for what he was doing.

Almost.

He quietly followed her until she reached the bathroom. He then made himself comfortable in a chair outside, waiting to hear his name. He spotted Daisy hiding in the shadows, and he gave her a little wave. She responded by flashing him a toothy grin.

"Oh, yuck!" Jemma's voice came from inside and Fitz smirked. His name was definitely going to come next. Sure enough, a second later, he heard his name. Just not how he had expected it.

"Fitz?" Jemma poked her head out and he looked up. She didn't sound scared at all. "Were you the one who brutally murdered the dummy in the shower and then spread pig's blood everywhere?"

So one plan didn't work. No matter; there were plenty more pranks hidden around the Bus. He responded to her question by shrugging a "yes".

"Okay." With that, Jemma disappeared back into the bathroom. That was followed by a thump (removing the dummy) and the sound of water running. Fitz shrugged to himself. It was only a matter of time before she screamed his name.

After her shower, they walked around together, Fitz being careful not to point out any particular thing, trying to keep Jemma on her toes. But with each prank they encountered, Jemma didn't seem at all phased. She'd simply comment on his creativity or how intricate it looked.

But it wasn't her praise that made him happy. He wanted her to get scared, which he did achieve in a couple of his pranks when he caught Jemma's little frightened gasp or slight jump. But she always covered it up quickly with praise.

They then finally settled down in the lounge with all the others - Coulson, May, Daisy, Mack and Elena. They dug into the spooky Halloween treats that Coulson had picked out and shared scary and funny Halloween stories from their childhood.

Daisy then started tossing candy corn at Jemma, who swatted them away, scolding her. A few landed on the floor behind the couch, and Jemma got up to retrieve them.

"Daisy! You've got to stop being such a child-" She was abruptly cut off my someone or something in the shadows grabbing her and pulling her back. She let out a shriek as she disappeared into the darkness.

Silence followed.

Fitz was the first on his feet. "JEMMA!"

He drew his ICER and made his way towards the darkness, ignoring the fact that no one else had moved. He suddenly blinked in fright as the lights came on, revealing Jemma in Robbie's arms, both of them grinning widely. Fitz gaped. Robbie nodded a hello. Jemma stepped forward, wearing a smug grin.

"I win."