The Big Bang Theory - Season 5 Episode 3 - Leonard and Amy get to know each other better, while Howard and Bernadette spend the weekend with Mrs. Wolowitz.
The Big Bang Theory - Season 5 Episode 5 - Sheldon and Leonard get invited to a party at Wil Wheaton's house, and Howard gets an out-of-this-world opportunity.
"The Recombination Hypothesis" - More than food appears to be on the menu when Leonard invites Penny to a romantic dinner for two.
Sheldon and Kripke square off in a series of sports-related competitions to win a coveted corner office at the university. Meanwhile, Penny feels uncomfortable accepting a gift from Amy.
The Big Bang Theory Season 5 Episode 19 - Sheldon opts to spend a weekend playing video games with the guys instead of attending a birthday party for Amy's aunt.
Big Bang's awkward attraction
The Big Bang Theory's Sheldon Cooper - the awkward, asexual but strangely lovable theoretical physicist with few friends and fewer social graces played by Jim Parsons - has become the poster boy for the show's loving embrace of the geek lifestyle. Ref. Source 4
The Big Bang Theory Season 5 Episode 22 - Bernadette reconsiders marrying Howard after learning about his s-xual history.
The Big Bang Theory Season 5 Episode 24 - When Howard and Bernadette decide they want to be married before his NASA launch, the gang rushes to put on a wedding.