SPOILER ALERT: Do not read until you have watched the Jan. 12 episode of “Crazy Ex-Girlfriend,” entitled “Nathaniel Gets The Message!”

When Scott Michael Foster first debuted on the CW’s musical comedy “Crazy Ex-Girlfriend,” he was coming into an already established show as a new workplace foe but also romantic interest for Rachel Bloom’s Rebecca Bunch. A well-off WASP who was working for his father, Foster’s Nathaniel Plimpton (the third!) seemed cold, calculating, and more often than not more like a machine than a man. But true to “Crazy Ex” form, being enmeshed with the offbeat characters of West Covina changed him, and Nathaniel got to show off a more sensitive side, which will only continue now that Rebecca has decided to take a break from their relationship to work on herself.

“She did some pretty wacky stuff to try and repair his relationship with his father — going to the extreme of stalking his dad and jumping to conclusions about this woman he’s going to see,’” Foster says. “She’s like no one he’s ever dated before, and he knew she was doing it for the right reasons but was doing it in the wrong way.”

Still, Nathaniel forgave Rebecca because he saw the relationship “as being worth it,” per Foster, which he notes makes things even harder on him when she ultimately tells him she can’t be with him right now.

“He spirals a little bit, and then you start to see him take a stand and make a decision and then he realizes he’s not quite strong enough to make a decision yet. He does a little bit of back and forth,” Foster says of Nathaniel’s journey to figure out what he really wants and what he feels he deserves. “He starts realizing that he might have to just let go and find someone who is good for him on paper. Whether he loves them or not — somebody that will be a typical girlfriend that will satisfy the parents. He starts realizing he has to move on from Rebecca; she’s going through her thing, and he can’t get in the way of that, no matter how much that hurts him.”

But while the show plays with the tropes of a traditional romantic comedy, it sets out to be much more than just that one genre. Early episodes may have seen audiences split off into camps of “Team Josh” or “Team Greg” and later “Team Nathaniel,” but it has evolved beyond that.

“I think at the end of the day — at the end of the show, whenever that is — the thing that everyone’s going to be is ‘Team Rebecca.’ She needs to be her team in figuring out her illness and getting healthy. The ultimate ‘ship is Rebecca and herself,” Foster says. “And honestly, I want the same thing for him. We have a bit of a cliffhanger this season, and I don’t know what happens, but he’s grown so much and become such a better person than he was before he met Rebecca, I think by the time this is all wrapped up, as long as he’s happy and healed in his relationship with his parents and knows what he wants out of life, those are the questions you always want a character to answer.”

In true ensemble form, even with Rebecca now off on her own journey of self-discovery and self-care, the other characters are being showcased in individual stories tackling their own problems.

“Sometimes you get a character and it’s that same character for six seasons and you never change, but this character, in a season and a half, has grown a lot! And that’s what I like about the show — that anyone in Rebecca’s orbit ends up growing and changing and becoming someone new,” says Foster. “It surprised me that we did that so quickly, but what I think is great is that people play the hero and play the villain at multiple different times in their lives.”

For Foster, being able to play so many different facets of the character so early in his run has led to musical numbers like the R&B-style “Let’s Have Intercourse,” hip-hop inspired “I Go To The Zoo” and club pop track “Hot Guys Have Problems Too.” The latter, which aired in the ninth episode of Season 3, peels back the notion that those who seemingly have it all on the outside don’t actually have anything more complex going on underneath to explore heartbreak for both Nathaniel and White Josh (David Hull), as well as a “quarter-life crisis” for Josh (Vincent Rodriguez III). These problems may not be as flashy or even long-term as some of the other issues explored on the show, but that lighter nature lent to more comedic commentary.

“I think originally it was going to be about fit, seemingly attractive white men, until Vinnie was added to the song,” Foster shares. “Obviously everyone has problems, no matter who you are, and it was fun to explore and fun to do the dance. We all got on diets to actually live up to the title!”

After originally auditioning with a Frank Sinatra song, Foster says that he is now “down” for anything the show throws at him — including a tango that he had to learn exclusively for the show and even a live episode, should the powers that be find a way to make that a reality.

“I’d done musical theater in high school and college, but I haven’t done them since, and it’s been like 12 years! So some of these dances are tough,” says Foster. “On days we’re not shooting, we still have to come in to rehearse the dances or record the songs. It’s a good challenge, but it’s definitely a challenge.”

“Crazy Ex-Girlfriend” airs on Fridays at 8pm on the CW.