AU where everyone gets a scar per lie. The type of scar is based on the lie. 

Warnings: mentions of abuse

When Pepper first started working at Stark Industries, her boss had always intrigued her. He gave off such a cliche celebrity persona, yet no scars littered his arms when she came to drag him out of his lab. Everyone she's met has only had small scars littered across their arms. She was included. Most of it was small white lies, such as "No, Mommy, I didn't have two cookies," or "Of course I'm working, what else would I be doing?" But one day, that all changed. Tony had gotten back from Afghanistan and locked himself in his lab. Of course, she would have to go down there to force him into social events and meetings, but no scars ever showed. This one time, he called her down to his lab. She walked in to a terrifying scene. It wasn't the fact that her boss had removed his arc reactor and was sitting in a chair meant for patients, nor was it the fact that he was surrounded by holographic screens that displayed his vitals. It wasn't even the deep hole in the middle of his chest, but it didn't help the situation either. It was the large scar, diagonal across his entire body. It was red and obviously deep. There were only two explanations: Afghanistan, or a huge lie. But Pepper stayed calm. She took a deep breath before heading in. She tried her best to ignore the scar, but failed and pulled it off as looking at the arc reactor. Tony told her to grab out a certain wire or pole or something, the details are fuzzy in Ms. Pott's brain now. What she won't ever forget, is when he went into cardiac arrest, and moments later said, "I'm fine." This wouldn't be such a big deal, if she hadn't noticed his wince in pain, and the small trickle of blood from the edge of the scar down, staining the side of his pants. 

"Tony, are you really alright?" Pepper asked again, now curious about the scar.

Tony sighed,"Not yet, but I will be. Eventually."

Pepper took a deep breath and demanded that he explained the scar. He obviously put up a fight at first, but his assistant was super terrifying, good for the business, bad for him.

"Well, it's a long story. It started as a child. Whenever I would get hurt, and show that I was in pain, Howard always told me, 'Starks don't cry. Stark men are made of iron.' Whenever I would burn my hand or get injured, or even get kidnapped and tortured, it hurt a lot for me as a child. So naturally I would cry for help. Anyone would do that, except for my dear old dad. He viewed this as a chance to make me tougher. whenever I would show pain, he would take me to the basement, tie me to a pole in the middle, and torture me in whatever way he saw fit. He would remind me that I was pathetic, useless, and a burden with a side of a whipping. He'd also remind me that he would trade me for Captain America the moment he would have the chance. I learned to just bury my pain and say that I was fine. Howard no longer abused me as much, and I learned to treat my own injuries. It just became habit to always say, 'I'm fine' whenever asked. I am not a fan of outright lying, but it was a survival tactic. I guess because it's just been one continuous lie, it only grows and doesn't add another small scar."

"Oh, Tony," Pepper cried while leaning in to give him a big hug, knowing he needs it. On receiving the act of affection, Tony looked startled and confused at first, but then melted into her arms while wrapping his around her.  They stayed like that for quite a while. 

As life went on, Tony had Palladium poisoning. Pepper grew suspicious, but knew he would come to her eventually. Sure enough, he did. Together they rediscovered an element. As Tony became part of the Avengers, Pepper and Tony started dating. She regularly checked on him and took care of him. She was always the one person Tony would go to for help. It took a long time, but eventually, he even trusted the rest of the team. And little by little, the scar faded and healed.