Callie has already moved on in life, and she seems to be dating someone fantastic. She also doesn't waste an opportunity to tell everyone how happy she is, making Arizona uncomfortable.

Viewers are yet to be introduced to Callie's new love interest, but according to showrunner Shonda Rhimes, it is going to be an interesting choice. Although Callie is bisexual, she falls for a woman.

"That felt natural and it's what the story is about and how it plays out. I really tried to stay true to the idea that she's bisexual but it's literally what the story is," Rhimes told The Hollywood Reporter about Callie's sexuality.

Interestingly, Arizona too is going to get a new partner, who will be introduced shortly. Although Rhimes did not reveal much about who the former couple will fall for, she did hint that their romantic relationship will be "pretty exciting ones."

As the season progresses, viewers will also see Arizona deciding what she wants to be now that Callie has moved on.

"I wanted to get back to the earlier seasons in which as I like to say, we're leaving the serious pain to the patients," Rhimes said. "Our characters have suffered enough. But also, Arizona is searching herself. We wanted to see her delve into and figure out what she wanted and needed. We're going to watch her try to find love, too."

It remains to be seen what Thursday's episode of Grey's Anatomy" entitled "Old Time Rock and Roll" has in store for Callie and Arizona, but it will see Arizona persuading her to give love yet another shot.

The official synopsis of the episode reads:

Owen suggests the interns learn a vital lesson on how to break bad news to patients' families, and Arizona's 90 year old patient reassures her that she's destined to find love again. Meanwhile, the sisters completely forget about the dinner party they're hosting for everyone.

"Grey's Anatomy" season 12 episode 4 can be watched online via ABC.go.com.