Tim: Well, that just lasted two hours. Well, two and a half. You try watchin' Brad Pitt in Interview with the Vampire and not feel a little conflicted.
An older and largely discredited (but by no means dead) trope in which a same-sex romance among young(er) characters is portrayed as "just a phase", which will be set aside later for more serious heterosexual relationships. This is more common with female characters than males for several reasons, including the idea that Girl on Girl Is Hot and the fact that Most Writers Are Male. It is becoming less common and more commonly subverted these days, when compared to its heyday in decades past, as homo- and bisexuality have gained quite a bit more acceptance. If you see something like this in a newer work, expect one or both characters to say something along the lines of "It's not a phase. I really am gay/bi," and if two characters are in a same-sex relationship, and one ends it on these grounds, it's common for the other to actually be gay and deeply hurt about them breaking it off, especially if it happens in a character's backstory in Yuri and Yaoi works.
Note that for various cultural reasons, this trope is still relatively popular in Japan where gay romance, especially between girls, is still considered by many to be innocent and immature, with the expectation that it will give way to said "serious" romance by the time they graduate. These relationships are commonly known as "S Kankei" or "Class S," and tend to have a Senpai/Kōhai dynamic to them. Attitudes do seem to be shifting, however, as polls from the late new tens and early new twenties have found that the majority of people, and the vast majority of under sixties, are in favor of legalizing same-sex marriage in the country.
May be motivated by Dating What Daddy Hates or trying for a Shock Value Relationship. Compare Experimented in College (a similar concept, in which a heterosexual character experimented sexually with the same gender but said experiments weren't romantic in nature), Pseudo-Romantic Friendship (where they're not in a sexual or physically intimate relationship, but they are emotionally intimate and follow many of the same tropes, again with the expectation that this will be replaced by "real" (heterosexual) romance when they grow up), But Not Too Gay (where the romantic aspects of a gay relationship are played down) and Bait-and-Switch Lesbians (where two characters of the same gender are presented as being in a romantic relationship, only to later reveal that they're not and are actually attracted to the opposite sex). See also If It's You, It's Okay, where a character hooks up with someone of the gender they're not attracted to.
Anime & Manga
- Invoked by Kaorin in Azumanga Daioh; upon being asked if her obsession with Sakaki means she's gay, she replies that she isn't gay, it's just a "teenage thing," and just to prove it, she wouldn't mind if Sakaki was a guy.
- In the backstory of Bloom Into You, Sayaka Saeki was in a romantic relationship with her senpai Chie Yuzuki, who broke it off because she thought they were outgrowing the whole "gay romance" phase. Subverted in that it wasn't a phase for Sayaka, who is a lesbian. When they run into each other in one of the manga's interlude chapters, said senpai apologizes for "corrupting" her into liking girls, much to Sayaka's confusion and anger.
- In the first season of Cardcaptor Sakura, Syaoran got quite flustered whenever he was around Yukito. Eventually he realized that he wasn't really attracted to Yukito, but rather his magical powers of the Moon from his true self, Yue, which Syaoran was drawn to whenever it interacted with his own powers. He then realizes that he's actually in love with Sakura.
- In the anime prequel Ga-Rei -Zero-, Kagura and Yomi — who are foster sisters — have a very non-sisterly relationship, with Yomi kissing Kagura on the lips and "skinshipping" her while they're bathing together; and Yomi is initially hesitant towards her arranged marriage to Noriyuki Izuna, though she decides to go through with it out of duty to her family and eventually grew to have feelings for him. However, Yomi's relationship with Kagura — sisterly or otherwise — is ruined when Yomi is manipulated into embracing a Bane Stone. Kagura is forced to kill her, and Yomi's vengeful spirit becomes the antagonist of the first arc of the manga. While Yomi is ultimately redeemed, both she and Kagura ultimately move on to male love interests — Yomi to Noriyuki and Kagura to Kensuke.
- To her confusion and consternation, Izumi develops a crush on Kagura, expressing intense jealousy of Kagura's romance with Kensuke. After an amnesiac Kagura rescues her from being imprisoned by the Supernatural Disaster Countermeasures Department due to housing Yomi's soul, Izumi confesses her feelings, insisting that she's not a lesbian and that her feelings are due to Yomi's "sisterly" love for Kagura bleeding over into her, but that she would be fine with hooking up with Kagura. Despite having amnesia, Kagura turns down Izumi's confession due to her subconscious love for Kensuke.
- Kämpfer: At one point, several characters are explaining the term "lesbian" to someone who has never heard the word before, and define it as "Women who are sexually interested in women while in high school". The sole lesbian character within the story, Sakura, turns out to be a Psycho Lesbian and the Big Bad of the entire story. She is also the the most promiscuous character, complete with her own abused and brainwashed harem of female Sex Slaves, with the ultimate goal of adding the protagonist to it.
- Secret of the Princess has Miu and Fujiwara's relationship start off like this, and only to keep Miu from telling anyone that Fujiwara broke a very expensive vase. They explicitly call it a practice relationship several times, but eventually they fall for each other and begin a true relationship.
- Tsugumomo: In the manga, Kanaka (mother of protagonist Kazuya) started a three-way lesbian relationship with her tsukumogami, Kiriha, and the local Physical Goddess Kukuri, at first justifying it as skinship bonding. Both Kiriha and Kukuri were shocked and upset when Kanaka later married a man, had children and ended all sexual contact with them, as neither were aware that Kanaka even liked men.
- In Scott Pilgrim, Roxy Richter is introduced as Ramona's roommate in college. It takes a second for Scott to get it, but when he does...
Scott: You had a SEXY phase!?
- Dr. Allison Mann of Y: The Last Man is a lesbian, but her college girlfriend Mercedes was not one. In fact, Mercedes seemed to think that lesbians don't really exist and that the only reason a girl would ever want to date another girl is to piss off her dad. She broke up with Allison shortly before graduation, saying that it was time to grow up and start acting like adults and that if Allison still wanted to piss off her dad, she should find a more mature way of going about it... like dating a black guy.
- In the Power Rangers Zeo fic "Memory Lapse", Shawna initially assumes that her past relationship with Tanya was this when she sees Tanya move on to date a boy. However, Billy and Alpha eventually help Tanya explain to Shawna that she actually dated Aisha rather than Tanya; when time was briefly changed during Master Vile's use of the Orb of Doom, Tanya was retroactively inserted into Aisha's place in Shawna's memories.
- This is explained to be almost ubiquitous in the centaur herds of Daily Equestria Life with Monster Girl. Given the nature of centaur stallions, no centaur filly would be interested in pursuing romantic relationships with colts, and so they seek romance from each other. However, homosexuality is strictly forbidden to the adult mares: given all the measures that have to be taken to allow reproduction and the limited gene pool, anyone who can get pregnant is expected to do so. As Cerea puts it, adolescence is the time for love and adulthood the time for breeding.
- Soda at 70 Proof; Rachel's mother has a problem with her daughter's crush on Fanny. She tells Rachel that she's going through a phase and that she had a similar phase in college until she met Rachel's father.
Films — Live-Action
- In Bilitis, the titular Bilitis has a girlfriend at school, Helene, but neither of them expects it to last, as Helene is leaving the school and suspects that Bilitis is only using her as a substitute for the handsome photographer Lucas, much as Bilitis denies having a crush on him.
- Implied in Mamma Mia! Here We Go Again, when Donna sings "When I Kissed the Teacher" to a female professor, but never exhibits any romantic interest in women after graduation.
- Scott Pilgrim vs. The World: Scott is stunned to learn Roxy Richter is one of Ramona's evil exes. When she insists it was just a phase, Roxy does NOT take it well.
Ramona: It was just a phase.
Roxy: Just a phase?!
Scott: You had a sexy phase?!
Ramona: It meant nothing, I didn't think it would count!
Roxy: It meant nothing?!
Ramona: I was just a little bi-curious.
Roxy: Well, honey... (cracks knuckles) I'm a little bi-FURIOUS!
- Theresa & Allison: Discussed as after learning that Allison previously was only with guys but wants to try women, Theresa rejects her because she's not interested in being someone's phase. She's soon drawn to Allison again though, and they become lovers. Allison does genuinely like Theresa from what the film shows, not just as a phase for her.
- V for Vendetta: Valerie's first girlfriend basically thought of their relationship as a phase. Valerie thought otherwise.
Valerie: I passed my eleven plus, and went to a girl's grammar. It was at school that I met my first girlfriend. Her name was Sarah. It was her wrists — they were beautiful. I thought we would love each other forever. I remember our teacher telling us that it was an adolescent phase that people outgrew. Sarah did. I didn't.
- Brie and Lara from Commencement by J. Courtney Sullivan are a slightly older subversion of the trope, occurring during their time at Smith College. The former claims that the relationship is just a college experiment and she'll go back to guys when she graduates. She doesn't, although she does question her relationship multiple times in the years after she leaves Smith.
- God-Emperor of Dune: due to some values dissonance, this is Moneo's (and presumably Leto's II also) opinion on lesbian relationships between Fish Speakers- something natural that they usually grow out of. Moneo said this during an argument with Duncan Idaho, who coming from another era is revolted by allowance for such pratices.
- Just Juliet: Discussed by Lena's dad when she tells him along with her mom that she's bisexual. Lena retorts gently that it isn't experimenting — she's just into girls along with boys, and to deny it would be denying half of herself.
- This trope was recognised by Agatha Christie in her novel Nemesis. Naturally, Verity is murdered by Clotilde, a Psycho Lesbian who couldn't handle Verity growing out of this phase and taking up with a local bad boy instead.
Verity had lost her real guardians, her parents, she had entered on her new life after their death, at an age when a schoolgirl arrives at having a "crush" on someone. An attractive mistress. Anything from the games mistress to the mathematics mistress, or a prefect or an older girl. A state that does not last for very long, is merely a natural part of life. Then from that you go on to the next stage when you realize that what you want in your life is what complements yourself. A relationship between a man and a woman... I think Verity adored Clotilde in an almost romantic way.
- In The Wheel of Time, teenage novices in the White Tower often become "Pillow Friends", which can range from being close friends to being in full-blown lesbian relationships. These relationships usually end when the novices become Aes Sedai, though some interactions later on indicate that they do sometimes continue; it seems to be a matter of personal taste. One woman haughtily dismisses the relationship as one for novices and not to be upheld by someone of higher achievement, whereas another thinks nothing of what she perceives as a sign that two women have been together for many years.
- In Batwoman, Sophie Moore admits to her husband Tyler that she had a lesbian relationship with Kate Kane in the military academy. Tyler demands to know how long this relationship lasted, and when told it lasted three years, he points out that's longer than any previous relationship he had before meeting Sophie.
Tyler: What was it between you two? And don't say it was just some drunk college hookup unless you were actually drunk for three years.
- In Being Erica, Erica revisits an episode from her university days where she explores her relationship with a lesbian classmate.
- Buffy the Vampire Slayer. In their first domestic squabble in "Tough Love", Willow accuses Tara of assuming she's doing this.
Tara: I trust you. I just... [looks down] I don't know where I'm gonna fit in... in your life when...
Willow: When... I change back? Yeah, this is a college thing, just a, a little experimentation before I get over the thrill and head back to boys' town. [pause] You think that?
Tara: Should I?
Willow: I'm really sorry that I didn't establish my lesbo street cred before I got into this relationship. You're the only woman I've ever fallen in love with, so... how on Earth could you ever take me seriously?
- Doctor Who. In the episode "Asylum of the Daleks", Oswin tells Rory that her first crush had that name, then amends to say that actually, it was "Nina", and it was a phase. We later learn that Oswin is one of the splinters of Clara Oswald, who is a case of Ambiguously Bi.
- Holby City, a Long Runner that launched in 1999 had a female Patient of the Week (who later returned in a different role a few years later, and then again in 2017 in another role) make reference to this in a throwaway line. However, this being produced during the Turn of the Millennium, it was treated less seriously than now and highlights how different things were in 2004 on the topic of sexual experimentation.
- You Me Her: Emma reveals to Jack after she becomes attracted to Izzy, who gives her a foot job under the table, that she's not the first woman or even second for her. It turns out she'd been with three women in the past already before him. At first he thinks this was just a lesbian phase, but Emma makes it clear that no, she's really bisexual.
- Magic: The Gathering's Chandra Nalaar pivoted from being an out-and-proud bisexual woman to suddenly describing her love of another woman as a "phase," complete with description of how much she loved manly muscles.
- In Gone Home, Sam's parents assume that her attraction to another girl is just a phase. Sam is not amused.
- In Kindred Spirits on the Roof, after Kiri admits her love for her teacher and club advisor, Tsukuyo Sonou, the latter tells her that it's just a phase she's going through during a confusing part of her life and she'll look back at this and realize it was a big misunderstanding when she gets older. Kiri, who really is gay, does not take this well, nor do the eponymous kindred spirits, who got rather pissed at Sonou's statement. Eventually, she does bring Sounou-sensei around and they do start a relationship, albeit a secret one.
- In El Goonish Shive, Nanase's mother thinks her relationship with Ellen is something she'll grow out of, an opinion Nanase is not happy with.
- Defied in A Joyful Life by Aerie and Joy as Aerie always always liked girls since she was young and even in adulthood still does while Joy has always like Aerie despite initially dismissing it as a phase.
- In Red String, Fuuko finds love with a woman named Hanae after she moves to Tokyo. When Hanae's mother discovers their relationship she chastises them telling that they need to grow out of it because it "Won't get them anywhere" (i.e. won't get them married), clearly disregarding their love as a "Class S" relationship.
- The Cleveland Show: In one episode, Cleveland calls "lesbianism at women's college" a phase, which is presented as a sketch of a graduation at which all the girls (in the front row, at least) turn to each other and say "We Need To Talk."