The Pulled Groin Extrapolation

Summary:  

Amy asks Leonard to accompany her to a friend's wedding as Sheldon was too immature at the last wedding they attended (and because he plays with model trains). At the wedding, the two bond over their mutual partners and Amy eventually convinces Leonard to dance. He eventually begins to get into it, but ends up pulling a muscle in his groin. As thanks, Leonard affectionately kisses her on the cheek, but Amy immediately misinterprets it as his falling in love with her, and immediately confides in Penny. The next morning, Leonard describes the evening to Sheldon, but inadvertently makes it sound like he and Amy had sex, prompting an unexpectedly jealous reaction from Sheldon, who hits him with his model train and tells him that she is "not for you!"

Meanwhile, Howard and Bernadette's already tense relationship gets worse when he mentions his intention to have her move in with him and his mother, and she demands Raj take her home rather than to the movie house. Later, she agrees to spend a weekend at Howard's house to try the idea for herself. The first night is disastrous, with Howard acting childishly and Mrs. Wolowitz being disgusting as usual, and Bernadette spends most of the night on the verge of tears. The next morning, though, she makes Howard breakfast in bed, only to get into an argument with Mrs. Wolowitz, sounding just like her in the process, and making Howard equally uncomfortable.

Title reference: Leonard pulling his groin while dancing with Amy at the wedding reception.

Production Code:  3X6853

External Links:  TVRage, Wikipedia, IMDB