“The Big Bang Theory” Season 9 episode 11 titled “The Opening Night Excitation,” which aired on Dec. 17, Thursday, marked a milestone in the relationship of Sheldon (Jim Parsons) and Amy (Mayim Bialik). The two spent their night together for the first time after five years of dating.

In an interview with Entertainment Weekly before “The Big Bang Theory” Season 9 episode 11 aired, Parsons said Sheldon always refers to it as “coitus.” Bialik added that the Parsons’ character mentioned his genitals, “which is really funny, too.”

Bialik also told the publication that she did not always assume that Sheldon and Amy’s first night together was going to happen eventually. She said she honestly felt like there are many different aspects of the two characters’ relationship and she thought it may have become a nonissue.

Likewise, Parsons said she had never imagined it because he would have never predicted almost anything “The Big Bang Theory” writers had done in the way they had done it. However, he pointed out that what the writers did with Sheldon and Amy’s first night together was “really skillfully handled.”

In addition, Bialik revealed that she did not know she and Parsons would have a bed scene. She said that fans had been asking if it was going to happen and for her, it was like asking about somebody’s virginity although Amy was just a character.

According to Bialik, she and Parsons talked about Sheldon and Amy’s first night together. She added that it was really special to them that they have had a relationship that is the longest-running nonsexual romantic relationship seen on TV.

In another interview with Extra, Bialik joked about shooting a bed scene with Parsons. She said, “I was surprised. I didn’t know we were ready.”

“The Big Bang Theory” Season 9 premiered on Sept. 21 on CBS. Joining Parsons and Bialik in the main cast are Johnny Galecki, Simon Helberg, Kunal Nayyar, Kaley Cuoco and Melissa Rauch.

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