Peter Quill is a member of the Guardians of the Galaxy who was taken from Earth as a child and raised by the Ravagers. Peter has many similarities to isekai protagonists who have been snatched from their original worlds. Although many isekai'd characters have no way to get back home, Peter never had any desire to go back home.
He is perfectly content with being in space, and exploring more than the singular fantasy world that most isekai protagonists are confined to. This allows fans to experience the excitement of visually going to a new world, over and over again. Despite having a unique hero of the genre, there are still many isekai clichés that exist in the movie.
10 The Protagonist Is Forcibly Taken From His Home World
Peter never asked to leave Earth. As a child, he ran out of the hospital, only to be taken by Yondu and the Ravagers. Although the original intention was to take Peter to his father Ego, Yondu Udonta decided against letting Ego anywhere near Peter once he realized what Ego did to his children.
Thus, Peter was taken in as a member of the Ravagers, which he didn't appreciate for most of his life due to Yondu's threats to eat him.
9 There Is No Language Barrier
Peter meets people from a large variety of worlds during his travels. Thanks to having a spaceship, he is able to pilot it to a large number of worlds. However, there seems to be no language barrier due to his translator implant.
The only person that Peter had difficulty understanding was Groot, who was the only main character who did not (technically) speak English. However, Peter would eventually learn Groot's language after spending a few years with him.
8 There Are Many Non-Human Characters
Nearly every isekai story depicts characters other than human. These characters are usually people with both human and animal characteristics, like Rocket Raccoon. The film also shows a wide variety of other humanoid aliens, who usually have green, purple, pink, or blue skin.
The alien characters are typically stronger or smarter than humans, having special abilities that are unique to their species.
7 Peter Has His Music Player From Earth
Sometimes characters who are sent to another world have the opportunity to keep an item from their original world. Due to some lingering attachment, they keep the item with them at all times. Without realizing it, the item that connects them to their original world quickly becomes a symbol of a past that is long gone.
Peter's music player is outdated, much like his knowledge of Earth. He often makes old references to things he saw when he was a child.
6 Peter Refuses To Go Back To Earth
Peter's Walkman represents one of the few good memories he had of Earth, as he had gotten it from his mother. However, he doesn't go back to Earth until Avengers: Endgame in order to fight Thanos and his army.
He doesn't want to be on Earth because he associates it with his fatherless childhood and the loss of his mother, which still causes him a lot of pain. After Thanos was defeated, Peter left the planet as quickly as possible.
5 Peter Has A Romance With Someone From Another World
The hero of an isekai almost always has a romantic interest in the new world. For Peter, this was Gamora. Similarly to many isekai protagonists, Peter was initially uninterested in having a lasting relationship with anyone. He had frequent flings, but only wanted to pursue a serious relationship with Gamora.
He has done a few selfless acts for her, giving her his space suit and even listening to her request after she was captured by Thanos in Avengers: Infinity War.
4 The Hero Is Overpowered
Peter didn't know it at the time, but he was actually only half human. On his father's side, he was half celestial. Celestials are able to manipulate the molecules around them, and they are so powerful that they are able to use the Infinity Stones, which is a feat most creatures aren't able to pull off.
Having this heritage allowed Peter to hold the Power Stone, which he used to defeat Ronan the Accuser.
3 The Heroes Are A Group Of Misfits
Most isekai protagonists travel with a group of people, usually parties or guilds. Peter is almost always seen with the other Guardians, embarking on various adventures and fulfilling tasks for whoever is willing to hire them.
Like many parties, Peter's group is a group of misfits, somewhat goofy characters brought together by specific circumstances. They have even grown close enough that they even refer to each other as family.
2 The Heroes Save The World
The Guardians of the Galaxy are actually able to save Xandar from destruction. Ronan hated the peace treaty that was formed between Xandar and the Kree, taking it upon himself to attack them in the hopes of destroying them.
The Guardians fought to keep Ronan from reaching the planet's surface, as it was capable of destroying it. When he did make it, they managed to steal the stone from him in order to use it against him.
1 The Hero Has A Tragic Backstory
Many isekai protagonists have a horrible first life. This is used to make the audience sympathize with them, and to cheer for the hero when they succeed in the new world.
Peter had a rough childhood. Since Ego had no interest in watching him grow up, all Peter had was his mother, who lost her fight against cancer. Moments before her death, she asked him to take her hand. Overwhelmed by his grief, he didn't, which is something he still regrets to this day.