I don't own The Big Bang Theory, or it's characters.

On Saturday, Sheldon did his laundry alone. This was not a common occurrence, it had only happened 5 other times over the last year. He relished the peace and silence. He spared only a moment to wonder where Penny was before gleefully going on with laundry night by himself.

On Sunday the guys came back from paintball to have lunch. While Sheldon cleaned up, Leonard went across the hall to get Penny for the meal. When he came back alone Sheldon frowned and asked where she was. Leonard shrugged and said she must not be home. Sheldon smiled when he realized they could watch Star Trek without any inane chatter.

On Monday Penny didn't show up for Thai food. When Leonard called to ask her what she wanted, she said she was doing laundry and wouldn't be over. Something nagged at the back of Sheldon's mind, but he quickly pushed it aside when Howard suggested a game of Warlords of Ka'a.

It took a burger to realize something was possibly wrong. They gathered at the Cheesecake Factory, as they did every Tuesday. They were seated at their table as always. Penny appeared a few seconds later as was customary. She took their order like usual. Then she walked away. That wasn't usual. No banal chit chat. No teasing. No inquiries about their day. Sheldon watched her hurry away with a frown. 4 minutes later she brought drinks. 9 minutes after that, their meals arrived. 10 minutes later she asked if they needed anything and set down their check.

"Penny," Sheldon leaned forward, "is something bothering you?" With hooded eyes, Penny turned on her heel and walked away. She did not even look at their table again.

Leonard sighed. "Are you and Penny fighting again?" he asked Sheldon.

Sheldon shook his head. "I am as perplexed as you."

Raj shrugged. "Maybe she is just having a bad day. She didn't speak to any of us, really."

They stood and prepared to leave, but Sheldon watched her at another table. She was smiling and laughing.

At 10:38 pm he heard her key in the door. Sheldon waited 15 minutes to give her time to change out of her uniform before crossing the hall and knocking. After his second round of knocks he moved back into his own home. Could she have gone straight to bed? That would indicate she was tired. That was a reasonable explanation for her moodiness.

On Wednesday they returned from the comic book store and ran into Penny on the 2nd floor.

"Penny, it is Halo night. Why are you dressed for dancing?" Sheldon asked.

"Because I'm going dancing," she replied in an even tone. The others looked back and forth between Penny and Sheldon warily.

Sheldon looked confused. "But it's Halo night." Penny skirted the group and headed for the stairs. Sheldon stepped in front of her quickly.

"Penny, am I correct in assuming you are upset with one or more of us?" he asked worriedly. Penny sidestepped him and continued down the stairs without a word.

On Thursday he was making up the weekly shopping list when he realized they still had a half gallon of milk. Penny had not been stealing any for her cereal or coffee. Something strange was definitely going on, so Sheldon decided to test her. He changed the wifi password.

On Friday she worked a double so no one saw her.

On Saturday she worked the morning shift, yet once again Sheldon found himself alone for laundry night. He had knocked when she came home and again before going downstairs, but she did not answer. He was coming up the stairs with his freshly laundered clothes when he saw Penny leave his apartment and cross to hers. He hurried up the remaining stairs, and got there in time to hear the lock turn.

Sheldon's temper flared up and he stomped into his own apartment. "I see Penny was here for the wifi password," he grumbled to Leonard.

Leonard shook his head. "No, she hasn't asked for it. She was just returning a movie I loaned her."

Sheldon frowned. "Penny borrowed a dvd? When?"

"Thursday. She sent me a text to ask if she could borrow my copy of Sherlock Holmes."

"Leonard, I think Penny is avoiding me," Sheldon said with a confused frown. "She has yet to speak to me, never answers my knocks or returns my texts."

Leonard sighed. "Sheldon are you sure you didn't do anything to Penny?"

"Of course I am sure." Sheldon declared.

Leonard shrugged. "Well, she's obviously upset about something. I suggest you give it some time and let her cool down."

Sheldon nodded after a moment. That seemed sensible.

Sunday evening Sheldon logged onto Age of Conan. After wandering around for a few minutes he saw Queen Penelope. As soon as Sheldor approached she logged out. Sheldon immediately stormed across to her apartment and knocked loudly.

When she didn't answer, he pulled out his spare key. Penny had engaged the dead bolt, which she rarely used and he did not have a key for. Sheldon hurried back into his apartment and grabbed his phone. He stepped into the hall and dialed her number. It went straight to voicemail. He slammed his door behind him as he went back into his place.

Monday Leonard went to see her at work. When he came back he handed Sheldon a stack of papers. Sheldon frowned when he realized it was the friendship agreement he had made Penny sign 4 years ago. He looked through it carefully and then froze.

Section 18.4

This contract shall be deemed null and void in the event one party causes malicious injury or harm to the other in the form of a physical, emotional and/or mental attack whether it be in verbal or written form.

This section was highlights and circled. In the margin Penny had written the date for the Friday two weeks prior.

Raj looked at him with a startled expression. "Dude! What did you do?"

Sheldon huffed angrily. "I haven't done anything!"

"Well, obviously something happened," Leonard said. "She's pretty mad."

"Well, what do you remember about that day?" Howard asked.

"I remember everything, Howard. I have an eidetic memory," Sheldon said in annoyance.

Howard rolled his eyes. "About Penny. Did you see her?"

"Penny drove me to my dinner with Amy Farrah Fowler. That was the only time we spent with each other," he replied.

"Did something happen on the date?" Leonard asked.

"It was a pleasant evening," Sheldon replied. "Amy and I had an intelligent discourse. The food was adequate. I do not even have any complaints about Penny's driving."

Leonard tapped the agreement in Sheldon's hand. "According to this, something happened."

Sheldon stood and went to his desk. He sent a video chat request to Amy and sat back to wait. 20 minutes later she accepted.

"Good evening Sheldon." she said primly.

"Good evening," he replied. "Amy, how would you classify our dinner the Friday before last?"

"Mostly amicable." Amy frowned slightly. "Why do you ask?"

Sheldon sighed. "It would appear Penny does not share that opinion."

Amy shrugged. "I am not surprised. She was not a very gracious guest."

"Um, hi, Amy," Leonard said as he entered the frame. "What do you mean by not very gracious?"

"She was very rude during my conversation with Sheldon. She interrupted several times and made loud objections to our discussion. On the ride home, she lacked the basic good manners to even say goodbye."

Sheldon was startled by Amy's words. He had not realized Penny and Amy had not gotten along.

"What exactly was the topic of conversation," Howard asked suddenly.

"We discussed Penny's promiscuity and it's effect on her decision making capabilities." she said calmly. "At first our discussions was stunted by Penny's refusal to participate or answer queries, but luckily Sheldon was able to provide the necessary information regarding her licentiousness."

Leonard looked at Sheldon furiously. "Yeah. I can see why she would be a little miffed at you."

Howard twisted his hands nervously. "Man, you're lucky all she did was terminate the agreement."

Amy looked at Sheldon speculatively. "Are you and Penny no longer friends? I am not surprised. She does not seem to be the type of person you would tolerate for long."

Sheldon looked at the floor for several seconds before turning back to Amy. "Good night, Amy. I must go now." He ended the video chat and turned to his friends. Apparently his only friends, now.

"Leonard, I do not fully understand what I have done." Sheldon said softly.

"Sheldon, you discussed Penny's private life with your girlfriend. In a public place. I'm willing to bet your girlfriend wasn't particularly discreet either. Do you not see how that is upsetting to Penny?" Leonard chastised.

"But it's not as though anything we discussed was a secret or untrue," Sheldon said. "And Amy is not my girlfriend."

"Okay, Sheldon, that's not the point," Howard said. "Listen, I'm going to say this because it's not a secret or untrue. Your girlfriend is kind of mean. And so are you at times. Together you're like this verbal assault team. And calling it an intellectual discourse when you begin picking apart the people around you doesn't stop it from being cruel. You think that no one should be offended by the things you say because you're smarter than them. If you were really as smart as you think, you'd realize that you treated Penny horribly."

"You ruined your friendship with Penny to further your friendship with Amy," Leonard said tiredly. He adjusted his glasses and sat down on the armchair. "I hope you are satisfied with the friend you've chosen."

When they traveled to the Cheesecake Factory the next evening Sheldon was feeling a bit nervous. He intended to speak with Penny and resolve their issue. Leonard insisted he had to apologize. While Sheldon disliked apologizing a great deal, he disliked the idea of losing Penny from his social circle more. Everyone was quite surprised to find Amy waiting for them outside the restaurant.

"I decided to try the food here since you insisted it was excellent," she said when they came near. Sheldon nodded and led the way inside. The hostess immediately seated them at their usual table and brought over an extra chair for Amy.

A few moments later Bernadette appeared to take their order. Sheldon frowned and looked around the room. "Where is Penny?"

Bernadette looked around the table tensely. "Sheldon, she asked me to take this table tonight."

He spotted Penny serving drinks to a table across the room. "But why," he whined. "Penny is our waitress. She is the one who brings my food."

Bernadette leaned down and glared at him. "Look, Sheldon, whatever this thing is between you and Penny, she is refusing to wait on you. You, specifically. When our manager heard her say that, he threatened to send her home. She said she'd quit before she brought you another burger. So you have two choices. Me or nothing."

Amy frowned at Sheldon. "The food had better be good to make up for the service."

Raj gave Amy a look of deep disgust and stood. He gave Bernadette a fluid bow before walking across the room to Penny. He took her hand and kissed it gallantly before leaving the restaurant. Howard stood and smiled wryly at Bernadette before turning and blowing Penny a kiss. Then he followed Raj. Leonard placed his napkin on the table and stood slowly. "This is what we were talking about, Sheldon. I hope the two of you have a pleasant meal." He waved at Penny and Bernadette before making his own exit.

Amy leaned across the table slightly. "Sheldon, how do you deal with such rude individuals?"

Sheldon looked across the room and watched as Penny disappeared into the back. With a heavy heart he gave Bernadette his order.