In " Preboot" it is revealed by the "human plus" Dr. Gross that are more humans outside of Ooo. This is further explained in the miniseries Islands, where it is revealed that roughly a thousand years prior to the main events of the series, a group of surviving humans from the Mushroom War fled Ooo on a container ship (as seen in Stakes) to escape from the vampires, oozers, and a comet. They eventually settled on a secluded island chain far from the mainland. Over the next thousand years, their community thrived and developed into an advanced technological society. While it was a veritable utopia, there were those few who occasionally grew dissatisfied with their rigidly structured lives and attempted to flee the island; these "hiders" were, in turn, hunted down and returned by specially trained "seekers." Finn, Jake, Susan Strong, and BMO went to the islands so that Finn could find out about his past and his species. Although various other humanoids exist in the Land of Ooo, most have been confirmed by the show's creator, Pendleton Ward, to be mutants, such as Penny, Phil, or the Old Man Henchman. [3] [4] In an interview in early 2012 (at the end of Season Three), Pendleton Ward stated that Finn was fourteen. In Issue 9, it is revealed that Finn had been called "Pen" in the original short because of his love for pens. Although originally, he was most likely named after the creator of Adventure Time, Pendleton Ward. A future Finn then takes his red sleeping bag when he and Jake leave to help Lady Rainicorn, also leaving a note of advice telling Finn to use his real name. This, however, is most likely non-canon.

Bad Little Boy," " The Prince Who Wanted Everything," " Princess Day," " Evergreen," " The Diary," " Friends Forever," " Be Sweet," " Orgalorg," " Varmints," " Cherry Cream Soda," " Broke His Crown," " Lady Rainicorn of the Crystal Dimension," " Five Short Tables," " Daddy-Daughter Card Wars," and " Ring of Fire" are the only episodes where Finn did not make an appearance. In " Lemonhope Part 1," it is shown that Finn has been taking classes at a school run by Princess Bubblegum, one of his classes being geometry. As of " Betty", Finn is no longer the last confirmed human because Betty Grof traveled through time from before the Mushroom War. In the Adventure Time: Distant Lands special " Obsidian", an older Finn appears. His hair has darkened and is now a darker dirty blonde colour rather than the golden-yellow blonde from when he was younger.Flame Princess is Finn's first and former girlfriend. Jake referred to Princess Bubblegum as Finn's ex-girlfriend in " In Your Footsteps," but Finn replied that they "never went steady."

Finn has a female counterpart: Fionna. She was previously thought to be fictional in Ice King's fan fictions, but in Adventure Time: Fionna & Cake, she, Cake and everyone else in Fionna-world was revealed to be real all along. Fionna shares the same last name as his biological mother, Minerva Campbell. Finn appears to not care for his hair much whatsoever, showed in how he frequently cuts it completely bald when asked (such as in " To Cut a Woman's Hair"), and in " Davey" when he shaves and slathers his hair in molasses, while BMO cries and claims Finn's "beauty is destroyed" and then says he looks like "the devil!"

About Finn the Human

In " Obsidian," he has become an adult man. His age is currently unknown, but it can be speculated that he's only a few years older, possibly in his 20's or early thirties as he is slightly taller, has grown a beard, and his hair color has slightly darkened becoming a dirty blonde from a golden/yellow blonde. Finn's narrative and impact on younger audiences has been compared to that of Harry Potter, the titular character in J. K. Rowling's book series of the same name. In particular, both characters were aged up as the series progressed, with Darren Franich of Entertainment Weekly saying that Finn "[aged] with his audience like last decade's Harry Potter kids." In Adventure Time: Fionna & Cake, it is revealed that the series takes place 12 years after the end of the original series finale, meaning that Finn would be 29 years old at this time.

Finn begins dating Flame Princess ( Jessica DiCicco) in the third-season finale "Incendium", after realizing that Princess Bubblegum is too old to be compatible with him. Although Flame Princess' fiery nature makes their relationship difficult, they try to make it work. Finn and Flame Princess eventually break up. Finn's relationships with both Princess Bubblegum and Flame Princess cause him to have to deal with rejection and reconciliation, and he emotionally matures as a result. Finn the Human's character arc has been highlighted by critics for its honest realistic portrayal of adolescence and universal struggles associated with coming-of-age. Brandon Zachary of Comic Book Resources described Adventure Time as "one of the most expansive fantasy series in modern history, centering around a kind but unassuming boy growing into a noble young man." Writing for Vox, Emily VanDerWerff called the series "this era's finest coming-of-age story", mentioning how Finn grew "from boy to almost-man, an adolescent who's slowly figuring out how to be both a good friend and a good person." Oliver Sava of The A.V. Club praised the episode "Breezy" for its relatable depiction of Finn's developing sexuality and his search for emotional fulfillment. Despite being mischievous from time to time, Finn is a very kind-hearted person. It's shown multiple times that he shows clear concern for others, even for those who have willingly hurt him, such as in " The Enchiridion," he returned the dollar to the giant (note that this was the very same giant who ate his beloved brother Jake and even kept insisting that he was dead). Furthermore, he shows clear contempt for anything that is done out of immoral reasons and a consistent drive for righteousness—to "do the right thing." In " Obsidian", he appears in his mid to late 20s as an adult and has a full-grown beard, along with a tattoo of Jake on his chest, implying that his adoptive brother may have died by this time. He also has more battle scratches. Finn and Jake frequently use math terms as catch-phrases and at times censors for curse words. However, they are shown to be terrible at math, as confirmed in the episode " Slumber Party Panic." (Examples of these words include: mathematical, rhombus, algebraic and math). This was utilized less frequently as the show progressed, though it still occassionally appeared.Finn's weight seems to fluctuate between episodes, with him seeming chubbier in some instances than others. Pendleton Ward stated on the "In Your Footsteps" commentary on the Season 4 DVD that his weight depends on how active he is adventuring, along with his diet, so it changes frequently. During the first five seasons, every alternate-reality, past-life, dream, and future version of Finn—with the exception of Fionna—is shown to have no right arm, or have an artificial right arm. These would include Shoko, Farmworld Finn, and the older Finns in " Mortal Folly", " Puhoy", and " Dungeon Train". Aside from his normal outfit, Finn can be seen wearing a cream-yellow sweater in colder areas such as the Ice Kingdom but would wear his pink sweater made by Princess Bubblegum occasionally. In " Holly Jolly Secrets Part II," he wears a dark blue sweater with Christmas decorations on it and a green scarf. Finn also wears white briefs that make their first appearance in " City of Thieves" when Penny steals his shorts at the end of the episode. In " Who Would Win," he was shown to wear a different pair with red elastic. Finn sleeps in red footie pajamas that appear in many episodes, but in the animated short, he sleeps in a red sleeping bag in his regular clothes. In the series, the sleeping bag is beige. As shown in " Memories of Boom Boom Mountain," the infant Finn eventually made it to Ooo, where he ended up alone in a forest. There, he went "boom boom" (Finn's word for defecation) on a large leaf and fell on it. He lay there crying until Jake's parents, Joshua and Margaret, rescued him from the wilderness and brought him to their home. They raised him alongside Jake, who, along with Jermaine, became Finn's adopted brother.