Sheldon Cooper and Amy Farrah Fowler finally consummated their relationship in The Big Bang Theory season 9's fall finale episode titled The Opening Night Excitation. The episode found Sheldon skipping Star Wars 7 premiere to be with Amy. He also gave her the most perfect gift and decided to be intimate with her.

Filled with Star Wars references, the episode found Leonard, Howard, and Rajesh watching the new Star Wars movie, while Sheldon and Amy took a big step in their relationship and engaged in coitus. By the end of the episode, Sheldon remarks that he enjoyed it and wants to make this (getting intimate) an annual event on Amy's birthday.

The Big Bang Theory co-creator Chuck Lorre told The Hollywood Reporter: "That line speaks volumes as to where this fits into his life. He enjoyed it, but his priorities are his work and research. Like a scientist, he investigated a sexual relationship and enjoyed what he found and sees no reason to pursue it until there's another birthday."

"Sex plays a very small part in his life, and I've always found that to be one of the most wonderful things about Sheldon's character: that he opted out of that part of life that everyone else assumes we should be obsessed with," revealed Lorre, before adding: "He's chosen not to be. From the very beginning, it's just not something that holds a lot of interest for him."

Showrunner Steve Molaro also dished on what next for Sheldon and Amy's relationship, and teased that the break up did good for the couple. "The separation was great for them, as people and as individuals and for their relationship. I don't know what would have happened had she not taken a stand and sent him this wake-up call where he realised just how much he wanted her in his life. And at the same time, she was feeling, 'I love this guy, but, boy, is he a lot of work! Is he worth the effort and the work to be in a relationship with him'?" he revealed

A new relationship agreement may show up in the upcoming episodes of the CBS show according to Molaro. "Ultimately, it came over the course of all these months of them being apart, where for her, the answer is: yes. And that's a nice place for them to be. As far as what happens moving forward and if there will be a Relationship Agreement 2.0 or not, that's to be determined. I'm sure he'll be thinking of it. Whether or not she will be OK with that is to be determined."

The next step in their relationship may have something to do with the engagement ring that Sheldon was planning to use to propose to Amy in season 8 finale. "That ring is in play. It's still in his pocket. We'll see what happens with it," teased Lorre.

If you missed Sheldon and Amy's big night, click here to watch the episode online (only in the US).