Author's Note: I'm sorry for the long delay. I finally decided to post the ending because another theme has inspired me to write another M rated Shenny tale. This is where the anal lovin' happens. Please read at your own risk. Also, I wanted to remind everyone that I do not own the characters or the show. Thanks to MyOwnStar and StrictlyOffKey for their previous beta work on this chapter.

Chapter Four: The Culmination

Sheldon put the items he was carrying on Penny's nighstand and placed the beach towel over the middle of the bed.

"Please remove your towel and sit on the bed."

Penny took off the towel and sat down. Sheldon grabbed it from her and put it on the floor. He kneeled on it and put his head in between her legs. Sheldon kissed the inside of her thighs before settling on her clit. She was still a little sensitive from his earlier ministrations, but he wanted her extremely relaxed before moving on to the highlight of their evening. He placed one finger inside her vagina and pushed it in and out. Sheldon was surprised to find himself enjoying the process. Painting her "blank canvas" (as Amy once called her lady parts) was a huge turn on. Penny smelled and tasted like a musky and overripe fruit. And the sounds she made in the throes orgasm were beautiful little chimes to his ears. But the best part was watching her writhe and come apart in his arms. Knowing that he was the one causing these strong reactions in her was deeply arousing.

After a few minutes he added another finger. Penny was moaning and undulating as an orgasm swept through her.

"Sheldon! Yes! Don't Stop! That feels so good! Fuck! YES!"

As she crested, Sheldon placed his other hand on Penny's stomach and gently removed his fingers from her vagina.

"That was so good Moonpie. I feel so boneless and relaxed right now."

"I was reading the Cosmopolitan you left in my apartment. It said being relaxed was important in completing anal sex safely and successfully. Let's move on to the next step. And just to clarify, only my Meemaw calls me Moonpie."

"Ok. Have your wicked way with me Sheldon."

Penny was smirking as she said this. Who knew that Dr. Sheldon Cooper, germaphobe and self-proclaimed expert on everything, was a sex god?

Sheldon removed his towel and had Penny lay down on the bed fully. He went on top of her and began to fuck her missionary style. He didn't use a condom as Penny was on the pill. Her inner passage was so wet and Sheldon was enjoying the sensations on his penis immensely.

The combination of the butt plug and Sheldon in her pussy was overwhelming. In a few minutes, Penny was panting and on the verge of cumming again.

"Sheldon, I'm so close."

"I think you are ready for the next part Penny. I must say the tightness is most pleasurable."

Panting loudly, Sheldon pulled out of her sheath. Sheldon cleaned off his penis with a wet wipe then placed a condom on it. He added some lube to his right hand and rubbed it up and down over the latex. After, he cleaned his hand with another wet wipe. Sheldon went over to Penny and slowly removed the butt plug from her anus. He cleaned it then placed it on the nightstand.

"Penny, are you ready for anal penetration now?"

"Yes, sweetie. Please fuck my ass."

Sheldon turned her over and helped Penny to her knees. He slowly pushed his cock into her anus. The tightness was amazing.

"Just relax and take some deep breaths. I'm almost in."

Once he bottomed out, Sheldon slowly thrusted. The sensations were intense. His member was in heaven and he started to moan in ecstasy.

"You feel so good Penny. My penis is being squeezed so tightly. Yes. Mmhhhhmm. I'm not going to last much longer."

"Sheldon! That feels so hot. My ass is burning, but it feels so good. I'm going to cum soon. Put the dildo inside me. I want to feel two cocks pounding away at me."

He stopped moving for a minutes and pulled out slowly. His hand reached for the dildo and he wiped it off with a wet wipe. He put some lube on it. Sheldon placed it in front of Penny's vagina and slowly pushed it inside as he slowly eased back into her anus.

She was now stuffed with two cocks. Sheldon started thrusting again and pushed the dildo in tandem with his movements. The added stimulation of the dildo against Penny's walls was intoxicating. His penis was enjoying the experience immensely. He started to thrust wildly into her anus. Sheldon also started to touch her clit with his free hand. The triple attack was haze-inducing. Penny was in heaven.

Sheldon! Oh my god! I can feel you and the dildo! Ohhh! Yes! Fuck yes! Keep fucking my ass and pussy!"

Penny was screaming and couldn't get enough. This was her fantasy come true. Sheldon was amazing and she couldn't believe what he was doing to her. Never in a million years had she felt such pleasure. Her pussy and ass both started twitching. The sensations were electrifying.

"Penny, I'm about to come! Your anus is so tight and the dildo rubbing against your walls is stimulating my penis beyond anything I've felt before. It's feels so good. Mmmhhhhhmmm."

"Fuck it's so hot! Harder! I'm cumming! Sheldonnnnn! Yes! Yes! Ohhh!"

Penny started squirting. At least Sheldon was prepared. The dildo in her passage caused the flow to aim downwards with the majority of the liquid landing on the beach towel. A little landed on his hand and groin area, but he was too involved in his own orgasm to care.

"Oh sweet baby Jesus! You feel so gosh darn good! I'm almost there! Penny! Penny! Penneeeyyyy!"

With one final thrust, Sheldon came and fell in a boneless heap on top of Penny as her orgasm tore through her body. Sheldon could feel the aftershocks on his spent member. This was the most intense sexual encounter of both of their lives. After taking a few calming breaths, Sheldon lifted himself off of Penny and moved to his side. He gently removed the dildo from Penny's vagina and wiped it off before placing it on the nightstand. His hands disposed of the condom. Sheldon then motioned for Penny to roll over and he removed the soaked towel and placed it on the other towel that was still on the floor. After, he gathered Penny into his arms and gave her a loving kiss. She then placed her head on his chest.

"You rocked my world Sheldon. I've never had an orgasm like that. We should do that again, but only on special occasions. I'm already feeling a little sore. It's good that tomorrow is my day off. People would wonder why I was walking funny at work. I love you so much and thank you for agreeing to experiment with me."

"I love you as well, Penny. For you, I am willing to explore outside of my comfort zone within reason. While I agree that the orgasm was exhilerating, I also feel that we should partake in this particular activity only sporadically. Although it was worth it, the preparation time is rather consuming."

Sheldon has come a long way since their meeting in the hallway. As he held a naked Penny in his naked arms, he was overtaken by a tenderness that filled his heart. She was his perfect mate. They were opposites, but both came from humble beginnings that strengthened their connection. He was quite happy to lay with her for the moment. However, his inner Wack-a-Doodle was warring with his sensitive boyfriend side.

"Penny?"

"Yes, Sweetie?"

Penny was enjoying post-coital bliss and snuggled deeper into Sheldon's side.

"We need to take another shower and change the sheets. The bacteria from our secretions and sweat is highly unsanitary."

THE END