The second half of Season 12 of "Grey's Anatomy" saw Meredith taking a step forward in her life since Derek's death by hooking up with Martin Henderson's character Nathan. Not many people are going to be happy with his hookup, and the first and foremost will be Owen, the character essayed by Kevin McKidd.

"That's going to come out, I'm sure, next season," McKidd told Entertainment Weekly. "I don't think Owen is going to be happy about that. He's almost becoming an unofficial brother to Meredith. Derek was his friend." McKidd added that he is a bit territorial about Meredith and there is also the fact that the last time Nathan got close to somebody Owen cares about, she died. "He might be being a little irrational when he finds out," the actor added.

Another person who won't be happy with Meredith's new relationship will be Maggie, as the finale saw her confessing to Meredith that she has started to fall for the new doctor.

Talking about how the hookup will reverberate in the upcoming episodes, Ellen Pompeo said that Meredith will have to keep her affair a secret. But she also noted that it was too soon to say if Meredith and Nathan will continue to get together.

Maggie has a crush on him, so Meredith can't really reveal what has gone on, because she has to keep it secret from her sister… [And] I'm not sure if the relationship, the sexual relationship, is going to continue or not," she told TVLine. "I think maybe they want to give the fans a little taste and see how they react first, and then they will decide what to do. Shonda is sort of savant in that way. She just gets these ideas, and she's very, very confident about what direction she wants her characters to go in. So maybe she has a plan for next year."

"Grey's Anatomy" will return to ABC in September.