Leonard loves Penny very much. The problem is that he is a little bit weird, so she has never noticed his feelings... until that day.
Penny used to sleep in a very noisy and uncomfortable bed and that is why she was always sleepy and tired. Leonard, noticing the situation, decided to help her by fixing her bed, "maybe this way she would like me", she tought. So, he got his tools and went to her apartment. She accepted the help and appreciated a lot, "it's very kind of you", she said.
The bed needed lots of repairs, so, he started his work. First, to show her his strong (in his thoughts) arms, he tried to lift the bed by himself to turn it down. However, he was so weak that he couldn't even lift a feather and, of course, he couldn't even move the bed. Penny saw the situation and ran to help him. He was very embarassed but she just laughed and told him not to worry about it because she wasn't going to tell it to anyone.
Then, the two of them started working together, once Leonard couldn't move the bed with his own arms. So, they spent the afternoon pulling the bed, fixing it, changing some screws and so on... The result was fantastic, the bed was brand new! No noises, very comfortable.
The afternoon had changed Penny's ideas about Leonard. They had talked a lot, about lots of things and she noticed how funny, sweet and smart he was. So, when he was saying goodbye, they were at the front door, he was ready to go... it happened! She kissed him, he kissed her, they kissed each other! Leonard couldn't believe, he was so happy!
From that day on they started dating and seeing each other very often. Now, every time Penny hears Leonard's voice she gets happy. Finally they managed to be together and their love is beautiful! They laugh when they remember that all started with a broken bed and weak arms and that their firs kiss was in that door where he had been so many times...