In Touch with Their Feminine Side and enjoy the things women are traditionally into, such as fashion or cooking/baking, and don't like to play rough, preferring quieter activities.
One key aspect to a boy being One of the Girls is that the girls do not see him as a potential Love Interest; he's "safe" as in they don't have to worry about him trying to get with any one of them or any ulterior motives. He and the girls are usually Like Brother and Sister, platonic Childhood Friends, or raised together in which the Westermarck Effect is in full force. Either way, the guy in the equation is not pushy about hooking up with his female friends. Which isn't to say that romance is not in the equation, though there will be much angsting about breaking up the friendship group.
A common plot with these types of men are their lack of male friendships and how they're seen as a "simp"note by other men. A consistent character conflict is just how "macho" they are compared to their male peers. Oftentimes, the guy in question is gay, which completely removes any romance option and the girls can just be friends with him. The gay guy is most likely to also have some Camp Gay characteristics, which will make him have a lot in common with his girl friends. A Gay Best Friend (especially if the series is more about the girls than him) usually falls in line with this flavor. But if the story makes it clear that he's into girls (which most of the time aren't part of the group, as he knows it'll ruin the dynamic) then he'll instead be Camp Straight.
The guy is always a Nice Guy or a nerd, and usually makes up the "guy" part of Two Girls and a Guy if not already The One Guy in a larger group. Also seen in the Harem Genre, with non-love interests of the main male character.
- Matsuri of Ayakashi Triangle is a rather literal example: The Only Friend he made before high school is a girl, and it's only after becoming female (but still seeing himself as a boy) that he made any more—three female, one male. Though he appreciates having one guy friend to talk to about certain things, Matsuri isn't bothered by the rest being girls, and was surprised when told opposite-sex friendships could be affected by (perceived) romantic tension.
- When Karai and April have a girl's night in The Chronicles of Karai Getting Her Shit Together, they invite Mikey. April cites that it's because he is really good at doing nails.
- Deconstruction in Syngenesophobia. The family has always acted like Lincoln was no different than his sisters, but now realize they've been taking the fact they have a brother/son for granted, because regardless of how in touch with his feminine side he is, he's still a boy and will have a different attitude towards certain things than his sisters.
- Flash Sentry in The Bridge is this in the Equestria Girls world. He'd known the girls since Kindergarten and was the one who got them into music.
- At the beginning of I Love You, Man, Pete is struggling to find a best man for his wedding because all of his friends are women. His search for at least one good male friend comprises the film's plot.
- Ducky, a character from California Diaries (a Darker and Edgier The Baby-Sitters Club spinoff), is 16 years old but he mostly hangs out with the other 13-year-old girls in the series. He had a book to himself about the dichotomy of his main friend group and his two male friends, one of which is more masculine and started hanging out with a rough crowd. Ducky was later outed by ghostwriter Peter Lerangis after the series ended.
- Andi Mack: Cyrus's closest friends are Andi and Buffy, two girls. He is friends with two other boys, Jonah and TJ, both of them more traditionally masculine than him especially TJ who's on the basketball team. In the first case, Jonah was a crush and in the latter, TJ was gay himself. TJ mostly had male friends into typically male interests, however.
- On one of the earliest Buffy the Vampire Slayer episodes, Willow is chagrined when Xander calls her a 'guy friend' who knows about girls (particularly since he's getting advice from her on how to click with Buffy). Later on, she's quietly pleased when Buffy tells him he's 'like one of the girls' to her.
- Degrassi: The Next Generation
- Marco does have male friends; in fact, they were the ones that helped him when he first came out. As the show went on, Marco starting hanging out with his best friends Paige and Ellie (who was a beard for him for a period) more often and then lived with them briefly while attending college. He has more things in common with Paige (love of fashion, boy-crazy) than his guy friends.
- After his male best friend JT was killed, nerdy Toby became this as his remaining friends on the show in his class were all girls. Shortly after JT was killed, Toby and Liberty kissed while trying to cope with the trauma, which sets one of the other girls off and she tells Toby to take the kiss back. Toby and Liberty end it and from that point, Toby is just seen as the friend and it seems like that how he wants it.
- Eli's entire social circle during his tenure at Degrassi were girls, including his girlfriend Clare. He's an off-putting goth outcast, and he's mentioned in the past that he's been bullied for not being like the other boys.
- Camp Gay Tristan mostly hangs out with his two friends Maya and Zoe (and previously Tori, before the actress left the show). During his tenure, he was contrasted with his older brother, a stereotypical Jerk Jock and later the macho hockey team that sort of picked on him.
- Derry Girls: James hangs out with the titular girls. At first it's because he's forced to attend the all-girls' school, as he's English and there are concerns he'll be beaten up if he goes to the boys' school. However, he does seem to enjoy spending time with the group, even taking Erin to the prom. A running gag is him being Mistaken for Gay, and during his one opportunity to make friends with other guys, he drives them all away by overdoing the macho bravado. The girls do seem to consider him one of them. Michelle even calls him a "Derry Girl" when she tries to get him to stay in Northern Ireland, instead of going back to England with his Mom.
- House of Anubis: Fabian's closest friends in the House were always girls. Despite his strong friendship with his roommate Mick, and later Eddie, he's always been the one to spend more time with the girls than the other guys. His Establishing Character Moment lumped him with Patricia and Joy, and even after Joy left and he and Patricia temporarily stopped being friends, he started hanging out primarily with Nina and Amber, instead. Fittingly, he's the least overtly masculine of all the Anubis boys, being a Nice Guy Extreme Doormat known primarily for being sweet and dorky.
- Played With on iCarly; Freddie, the titular webshow's tech producer, is part of the Two Girls and a Guy trio with Carly and Sam. In one episode he lamented the fact that he did not have any male friends to hang with. However, as the series went on, he gained male friends as part of nerdy clubs. Also unusually for the trope, there was an underlying romantic tension between the three of them that they tried to ignore in order to not make their friendship any more complicated.
- Katy Keene: Jorge is the only male main character that's friends with all the female leads, and Katy was his Child Hood Friend. Jorge is very Camp Gay and he's also a Drag Queen and has serious issues with having to conform to traditional masculine ideals.
- Victorious: Robbie is often grouped in with the girls due to being effeminate compared to the other guys in the group. For instance, he stays in the girls' hotel room when the group visits a foreign country.
- Granblue Fantasy: Ladiva, a Campy male Draph ally with feminine behavior who often hangs out with female playable characters, especially when cooking. She also thinks that a Draph like herself doesn't have to be masculine despite their extreme musculature (remember: masculine Draphs are naturally huge). She's mostly associated with feminine pronouns, as the Japanese text has her using "Atashi" (usually used with girls) when talking about herself and the official English translation refers to Ladiva with she/her, though it's ambiguous if it's meant in the way that she's just really good at keeping up a drag Kayfabenote or she's Transgender.
- In A Souls Tale, Lucas was mostly raised by his mother, and seems to prefer the company of girls like Astrid, Liz, and Sylvie rather than boys.
- Leslie from The Amazing World of Gumball is mostly friends with the girls, being seen with the other girls in Molly's treehouse in "The Pressure". He's apparently good at giving relationship advice, and it's often implied that Leslie is gay. This is also one reason why many fans mistake him for a girl.
- Ed, Edd n Eddy: Jimmy prefers to hang out with Sarah and Nazz because he has similar interests to them. One episode has him hang out with the two as opposed to going go-karting with Kevin, Jonny, and Rolf. In another episode, he's part of the cheerleading squad along with Sarah and Nazz, while all the other boys are in the football team.
- The Loud House: In "Roughin' It", Lincoln realizes that he frequently hangs out with his sisters and worries they're turning him soft, leading him and Clyde to take a boys-only camping trip.
- Milo of Pepper Ann is the guy in the Two Girls and a Guy trio the main character is in. He even has A Day in the Limelight where Pepper-Ann and Nicky are busy, so he tries socialising with other guys (which it turns out he's quite awkward at — at least until he's able to explain that boys and girls aren't so different.)
- My Little Pony: Friendship Is Magic: Spike spends most of his time with the all-female Mane Six, holding especially close bonds with Twilight, Fluttershy, and Rarity. It isn't until much later in the series that he is shown spending time with other males (and even then, that group consists simply of himself, Big McIntosh and Discord, and the three of them make up the majority of regularly appearing male characters on the show).
- She-Ra and the Princesses of Power: Bow, whose only friend for a long time is Glimmer. He eventually becomes also the closest friend to Adora and gets casually along with the other princesses. He does have also a male friend/target of admiration, Seahawk, but his female friends vastly outnumber him. Justified as Bow is Glimmer's childhood friend and he specifically works for the Rebellion, where the strongest combatants are magical princesses. The egalitarian nature of the show also diminishes the implications of this trope in Bow's case.
- Justified in the case of Steven Universe/Steven Universe: Future: the titular character's Parental Substitutes are aliens coded as women, his best friend and later partner is a girl, and many of the people/gems that have made an impact on Steven have been female(-coded). The series is already pretty heavily dominated by female characters (the number of main male characters including Steven can be counted on one hand), though technically the gems have No Biological Sex. Steven doesn't have a complex on being/acting masculine; he's fond of the color pink, cries openly, and his greatest strength is his empathy.
- Ready Jet Go!: Because Mitchell does not have any male friends who are his age (Jet and Sean are both older than him), he hangs out with Mindy and Lillian, who gladly accept him into their circle. Mitchell isn't hypermasculine at all and embraces his feminine side. In fact, he wore Mindy's sparkly unicorn helmet in "Try and Try Again".