This is a list of songs that are mentioned in the book (by order of appearance) and outside ones I've heard that I feel fit the characters/situations in Saving Grace.
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"Kiss the Girl" - The Little Mermaid
This song is mentioned in Iron Man 2 while Tony and Grace are watching the movie, and it prompts Grace to ask Tony when he's going to kiss Pepper. The lyrics are urging Prince Eric to kiss Ariel instead of being shy and hesitating. I think, in Pepper and Tony's relationship, their first kiss was hesitant. They'd first tried it six months prior with no success due to hesitation (which mostly came from taking Grace's feelings into account), but they finally got it together, and, according to Rhodey, looked like two seals fighting over a grape — but, hey, at least they kissed. I also think Grace and Peter were hesitant, as they took a bit to actually lean in at first. Just kiss her already!

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"California Love" - 2Pac
This is played at Tony's party in Iron Man 2. California was the setting for the first two movies, and it talks about having a party. Which Tony did. The lyrics are decidedly not clean, so we'll just not link that here.

"Another One Bites the Dust" - Queen
This song played while Rhodey and Tony were fighting at Tony's party in Iron Man 2. I'm sure I don't have to detail this story's connection to dust... It's inspired by an actual shooting from 1929, but you know how it goes anyway.

"Stayin' Alive" - Bee Gees
This song was also in the book, when Tony was driving Grace to the compound at the end of Age of Ultron. Essentially (according to Genius), the song is about New York — survival in the streets of it specifically, though that doesn't apply here — and New York is the setting for nearly the whole story (besides Malibu, space, Wakanda, and a few other, minor places). And, aren't the characters essentially just staying alive — and/or trying to — half the time? Also, the song mentions, "The New York Times' effect on man." In this case, to fit the book, I think it can be applied to Tony and Grace's situation early in the story — the media/news trying to get a glimpse of Grace, to get Tony to talk about her and her mother and explain things. They wanted personal details, they wanted in on her life, and Tony wouldn't allow that. That certainly affected the both of them. You know how this one goes, too.

"Can't Help Falling in Love" - originally Elvis Presley, covered by twenty one pilots
This is another song that was included in the story, this one as Grace's ringtone for Peter and the song he sang to her over the phone, though I didn't specify which version I was thinking of in the book. I think the lyrics actually fit Peter and Grace's situation. They connected pretty quickly; by the end of the Berlin trip, Peter wanted to know everything about her, and Grace was enthralled by him — that fast. They basically fell in love within a period of about two to three months. But some things are meant to be.

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"L. O. V. E." - originally Nat King Cole, covered by Michael Bublé
This song is played during Peter and Grace's homecoming dance. This song, originally, was going to prompt Peter and Grace's first, "I love you," but then I had Grace join the fight at the end, and them saying it on top of the Cyclone just felt right. The lyrics themselves seem to me to describe the sort of honeymoon phase of love, right at the beginning, which is where Peter and Grace were at the time. Their love eventually matured, but I feel like Peter would still turn this on and dance with Grace in the kitchen on occasion after they've been married for years and are tired that day from taking care of the kids. Or maybe from stopping another bad guy trying to end the world. Possibly both.

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"La Cucaracha" - it's unclear
The horn of the "ugly brown van" honks to the tune of this song in Endgame... The title means "the cockroach" so that's fun. New York City probably has cockroaches, and that's where a lot of the story took place, so... there's a connection? You know how it goes.

Bonus: Tony called Loki Rock of Ages in The Avengers, which references a whole musical of the same name.
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"COUNT ON ME" - NEEDTOBREATHE
This song is basically a lot of characters to Grace. Of course, there's Tony, who is ready to drop everything at a moment's notice if she needs him. Then, Pepper, Happy, Peter, Nat, Wanda, even Sai — the list goes on. Thanos said it himself: she's very important to a lot of people. The moment she's in trouble, there are people who will do basically whatever they can to help her. She can count on them.

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"RUNAWAY" - half•alive
This is the song of character development — Peter's and Grace's. Grace's happens first, due in part to Wanda and Fury. She realizes her own capabilities and responsibilities, and basically comes to find that, no, she is not, in fact, invincible. She wanted to run towards danger and away from where she was best fit to be, be it far away and safe, or doing the little jobs that someone's gotta do until she works her way up with experience. Peter was much the same way, thinking he was ready to be an Avenger, to fight the bad guys all on his own, but, in the end, he realized he didn't need to run away from the life he had — a good aunt/mom, good friends, a good school, and a totally great girlfriend.

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"Bring Him Home" - Les Misérables
This is song is Tony about Peter in Infinity War. The situations are honestly insanely similar, and I'm surprised I didn't realize it sooner. Tony is Valjean, Peter is Marius, and Grace is Cosette.

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"My Blood" - twenty one pilots
Who would I be if I didn't put at least one other twenty one pilots song on this list? "My Blood" is kinda in the same vein as "Count On Me," but I think it applies more to a sibling relationship — especially considering the music video shows brothers. I would apply this song to Grace and Harley, and to Grace to Morgan.

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"This Place is a Shelter" - Ólafur Arnalds
This is a classical piece actually, so it has no words. I'm mostly going off of the feelings it evokes, along with some inspiration from the title. There's a lot of sadness in this piece, as well as in Saving Grace. The shelter that the title is talking about here, for Grace, is the arms of her loved ones. In the heartaches of her life, people have been there to hold her through them — Tony, Pepper, Nat, and, lastly, Peter. I can see this music playing over any one of those instances, but especially the last one, at the end of the book.

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"DNA" - Ludovico Einaudi
Another classical piece. This one is also drawing from the title as well as the feelings the songs gives. This song, to me, has ups and downs. There are sad parts — struggles — but there's also lighter, happier parts. That coupled with the title makes me think of Tony raising Grace and what he felt while doing that. It was difficult for him, not just in the beginning, not knowing what he was doing, but during the times included in the book. He wanted to leave a better world for her, to keep her safe from the bad in it, and, especially in the end, for her to be happy. Sometimes, he fought to do that. But there were definitely good moments — wonderful moments — when he could really look at her and see who she'd grown up to be, and he was proud. And he could take a moment and just sit in that, and know that he must've done something right.

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"Banks" - NEEDTOBREATHE
Yet another NEEDTOBREATHE song, as they recently released this one and I thought it was perfect. They tweeted that it was a song for the women in their lives — a song of support and encouragement — and I think it's definitely Peter to Grace, especially after they get married. He wants to support her in all her endeavors, guide her, help her when she needs it, and "hold [her] close, but never hold [her] back." He's the banks to her river.

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