Although the Marvel movies in the MCU are typically focused on action and adventure, there is still a great deal of romance throughout the franchise. There are countless couples and close friends who may be platonic or romantic at some point in the franchise.
In between the fighting and the jokes, there are serious moments of sacrifice, adorable romantic moments, and moments of deep love, connection, and respect between the large cast of characters in this insanely popular franchise.
Peter And Gamora Dancing
Although Peter and Gamora might not be the best couple in the MCU, they had some adorable moments throughout the movies they've appeared in. This scene between Starlord and Gamora is a funny and intimate moment that begins to allude to a possible romance between the two in the first Guardians of the Galaxy. Although the scene ends with Gamora almost attacking him when she doesn't know what he's doing with his hips, it's still a fun and cute moment between the two.
T'Challa Listening To Nakia
Most of Black Panther focuses on T'Challa grieving his father's death and adjusting to his new status as the leader of Wakanda, so there isn't much time for romance between him and Nakia. The two were in a relationship that seemed to fall apart when Nakia didn't agree with Wakanda's isolationist policies, which T'Challa listened to her (and Erik) by the end of the movie and decided to make Wakanda globally recognized and willing to help those in need. Although not particularly a romantic gesture, it still shows how much T'Challa cares about Nakia and truly listens to and respects her opinions and ideas.
Tony Proposing To Pepper
It's a small moment in Spider-Man: Homecoming at the end of the movie where Peter decides not to join the Avengers as Spider-Man just yet and grow up a little before committing to the team. Peter acts like this is a test from Tony, but hilariously, Tony had a whole room full of members of the press ready to hear big news so he decides that maybe now is the time to propose to Pepper.
He asks friend and security detail Happy if he has the ring and he says he's had it since 2008 (when Iron Man was released) and he throws Tony the ring to presumably propose to Pepper in front of the press.
Janet Going Subatomic
Janet chooses to sacrifice herself to save everyone, shown in a flashback in Ant-Man and the Wasp, including her partner Hank Pym who had damaged his suit and couldn't sacrifice himself to a fate possibly worse than death. She doesn't hesitate even though it's a big sacrifice and Hank finds it admirable even though he misses her dearly and works every day to try to find her and save her in the quantum realm.
Maria Reminding Carol Who She Is
Most of Captain Marvel finds Carol Danvers slowly remembering her past and everything comes rushing back when she finds her old best friend and fellow pilot Maria and her daughter, Monica. Carol has had a difficult time throughout the whole movie figuring out who she is and wondering if she's part of the bad side, but everything changes when she reconnects with Maria. Whether romantic or platonic, Maria and Carol have a bond that can't be broken.
Vision Sacrificing Himself For Wanda
In Infinity War, the Avengers fight Thanos and try to find the infinity stones before he can collect all of them and disappear half of the population. The mind stone is connected to Vision and the team knew that they had to remove it from him to destroy it, but it would most likely destroy him. Wanda fought against it and Shuri attempted to remove it safely with Wakanda's technology, but she didn't succeed. In an emotional scene, Vision pleads with Wanda to destroy the stone to save everyone.
MJ Keeping Peter's Secret
MJ found out that Peter was Spider-Man near the end of Spider-Man: Far From Home right when the two begin a relationship. Peter doesn't even have to ask her to keep the secret as, of course, MJ is going to keep and respect his secret until, unfortunately, Peter's secret is revealed to the world as Mysterio's last trick. MJ and Peter's beginning to their relationship is adorable and awkwardly charming start to their high school relationship.
Steve And Peggy's Dance
Steve decided to stay in the past so he could live his life with Peggy, choosing to spend his life with Peggy over everyone else, after time traveling at the end of Avengers: Endgame. Before Steve sacrificed himself in Captain America: The First Avenger he promised Peggy a dance and finally delivered.
It's an adorable moment as he shows up unexpectedly and Peggy and Steve have a slow dance together and Steve appears at the end of the movie as a happy elderly man who gives the shield to Sam.
Steve Saving Bucky
Steve Rogers and Bucky Barnes have a close relationship that is oftentimes tinged with tragedy as their story started around World War II when Bucky joined the U.S. forces and Steve became Captain America. Steve was roped into making USO appearances and not able to fight alongside the U.S. forces like he wanted to at the beginning of Captain America: The First Avenger. Bucky and his regiment were missing in action, but when Steve heard that Bucky's regiment was being held by HYDRA he dropped everything, disobeyed orders, and went on a rescue mission to save him.
Valkyrie Sacrifice
Valkyrie in Thor: Ragnarok has a flashback scene where she remembers fighting Hela alongside the other Valkyrie fighters. It's a beautifully shot scene that conveys the heartbreak Valkyrie feels as all of her fellow warriors are killed by Hela. There's a moment in the flashback where Valkyrie has a connection with one of the other fighters, Valkyrie actor Tessa Thompson has said that she views this character as Valkyrie's partner, and watches as she sacrifices herself to hide Valkyrie from Hela making her the one survivor of the battle.