Their friendship was one of true yin and yang. Always pushing and pulling, testing and being tested. They were opposite balancing the scale of their universe. They battled and fought; cared for and sought comfort.
Looking back they should have seen it coming. As soon as Lenard left for six months what hope did they have?
When they collided it was equal parts fierce and passionate as it was utterly right. Penny led as Sheldon followed close behind. Later Penny would admit it was one of the best sex of here life, simply because of who it was with.
They kept to themselves, needing no one but the other to satisfy their every want and need. They sat through the others crappy tv shows somehow making the viewing better with the witty comments. She drove him around while he cooked for her. She suffered through the train store while he forwent Thai night.
Penny was the illogical love he couldn't get rid of while Sheldon forced order into her wild life.
They still fought often. Perhaps even more. Though now instead of a verbal apology he would show up at her door in his best suit and take her to her favourite restaurant while she would clean the apartment, his apartment, from top to bottom just the way he liked it.
The day Leonard returned was the worst day of Penny's life.
He had come to the final conclusion that he couldn't betray his best friend by being with her. She cried harder then she ever had for some guy. Because he wasn't some guy.
Sheldon lasted exactly 6 hours and 37 minutes before he snuck over to her apartment and let himself in.
When he confessed to needing her more than he needed his own brain she dragged him into her bed. That night they put all their love into sex. It was raw and slow and burned like an inferno. It was beautiful.
Though the night was perfect they made a colossal mistake.
Three weeks later Penny threw up for the second time that morning after starring at the positive pregnancy test. Sheldon immediately proposed. Still they kept their relationship a secret. Scared to break down the walls of their own private sanctuary.
That all came crashing down when the hormones kicked in.
Normally Penny could take any snide comments from being a waitress but with a baby growing inside her the comment of she should "whore herself out to feed her family" didn't bounce right off.
Sheldon could tell something was wrong the moment she stepped through the door and, to the astonishment of everyone in the room, put down his controller without pausing. She started crying the moment she saw him get up and he could never stand to see her in pain. She melted against him, defeated. He built her back up.
The words of "I love you", "marriage", and "baby" finally kick started their brains and the rest of the guys, now able to close their mouths, left the apartment and them alone. He eventually got her calmed down enough to get her to his bedroom. As Penny drifted off to sleep in the arms of Sheldon she knew everything was going to be okay.