It's not easy being The Chick and Action Girl at the same time, you are often the target of being attacked by the bad guys and having next to no self-defense ability. And then there are the times where the only thing between the world being destroyed is you and possibly the magical McGuffin that allows only a girl to transform or let them use the item.
Who knows why the device won't work for guys, a slight technical oversight perhaps, maybe because it runs on certain sources of energy? But who knows. The Girl-Powered Device ain't going to work on men at all, for some reason, and no attempt is made to get it to do so.
It is often used in the Harem Genre in japans pop-culture (mainly to justifing a World of Action Girls-/All Women Are Doms, All Men Are Subs-setting). The main character is usually the The One Guy. Often results in Sliding Scale of Gender Inequality where men get the short end of the stick.
Subtrope of Gender-Restricted Ability. See Virgin Power when the requirement to use the powers is not being female so much as being chaste. See also Barrier Maiden. If a transgender woman finds that the power works for her just as well as it would for a cisgender woman, she is a Supernaturally Validated Trans Person.
- The Humongous Mecha of the Alternate Universe in Dual! Parallel Trouble Adventure only work for girls, with the exception of Kazuki. The reason Kazuki can is because his parallel twin is a Mecha. The reason only girls can pilot the Mecha is a limiter that was put in place, because men could make them produce Light Hawk Wings, which makes this an inversion.
- In Sailor Moon, only girls can be Sailor Senshi, end of story. Tuxedo Kamen is the closest the series has to a male Sailor and represents Earth in the lineup, but his power comes from the Golden Crystal, the counterpart to the Silver Crystal, not a Sailor Crystal like the rest of the Senshi. This is what justifies the idea of Sailor Earth.
- Only girls can become magical, well, girls, in Puella Magi Madoka Magica. There's no specific reason why there couldn't be a magical boy, but Kyubey and the rest of his alien race specifically target pubescent girls because their emotional output is much higher than any other human demographic; it's just not worth the investment for them to try to harvest anyone else.
- Valkyria Chronicles has the Valkyria, who seem to be a race of only women. Men don't even bother picking up Ragnite lances as weapons.
- Then came the Valkyrie power armors which evened out the playing field, as well as other projects which gave them One-Winged Angel forms, at the cost of their sanity.
- The priestesses of the Fushigi Yuugi stories are, as the name implies, all female, for no other reason than the four gods just aren't into guys. Most of the Seishi are men, however.
- Name a Comic Valkyrie Manga such as Freezing for example, the Pandoras (aka girls) are the actual combatants in the Battle Couple, the guys only purpose is to hold the bad guys down to allow the girls to beat them up
- My-HiME and My-Otome, only a girl (and in My-Otome, a virgin) can have a CHILD. This doesn't stop Yuuichi from trying to help out, nor Mashiro (in the Manga, where she is really a he) pulling a CMOA in the end.
- In VITA Sexualis, Shirou acts a conduit for allowing the already powerful female cast to transform and fight.
- Strike Witches is a subversion as non magic powered weapons can damage the Neuroi, but because it takes longer and more ammo to kill them, Witches are needed to quickly finish them off.
- The titular Infinite Stratos combat exoskeletons are only usable by women, with the sole exception of the main male protagonist. Apparently according to the inventor, this wasn't intentional, but she won't care to fix this, nor find out why the main character can use it despite his gender.
- Kämpfer, all the fighters are female and the only one who isn't goes through a Gender Bender to do so.
- Gender inverted in D.N.Angel since only males can bear the "Dark" gene that allows them to take on their magical boy form.
- The titular planes on Simoun could only be piloted by girls, who had to kiss each other to activate it.
- Questionably present in Gunslinger Girl. It's explained that only children can be turned into cyborgs, and never explicitly stated that they have to be girls, but we never see any sign of a male cyborg.
- While the actual handlers in Asura Cryin' can be of either gender, the Burial Doll are always girls.
- All of the CR-Units are manned by girls in Date A Live as the Director who makes the Realizer Units is a Handsome Lech.
- While the sole consistent of becoming a Pretty Cure is being a girl, it seems to flip flop on other matters:
- Both Fresh Pretty Cure! and Smile Pretty Cure! had a "Freaky Friday" Flip episode which had a Cure swap minds with their fairy partner. While the Fresh episode allowed Tarte-in-Inori's-body to transform into Cure Pine just fine despite Tarte being male, the Smile episode forced Miyuki-in-Candy's-body to transform into Cure Happy despite both being girls.
- Age is another odd thing. Young girls like Suite Pretty Cure ♪'s Ako and Doki Doki Pretty Cure's Aguri are able to transform and older teenagers like HeartCatch Pretty Cure!'s Yuri and KiraKira★Pretty Cure à la Mode's Akira are shown being able to transform, but anyone older tends to flip flop as the post-series novels for Fresh and Smile have shown the girls transforming ten years later, yet an adult chosen to be a Cure in HappinessCharge Pretty Cure! can't get her stone to create a PreChan Mirror
- The titular Infinite Stratos can only be piloted by women. The protagonist is the first male who can operate said device.
- In Mato Seihei no Slave, only women can eat the Mato "peaches" that grant super-powers to fight back against the mindless beasts coming from that dimension, who seek to kill and eat all life on Earth.
- Inuyasha had an evil version with the Salamander demon. Only women could have been force-fed the evil salamander egg that would possess their bodies for as long as the hatchling lived inside their bellies.
- The titular Witchblade can only be wielded by women, and has been by several famous warrior females throughout history like Jeanne d'Arc. Also it strips off all your clothes and leaves you wearing skimpy armor... we wonder why.
- The Darkness has both an inversion and an example, only men can be hosts to the demonic power of the Darkness, and only women can be possessed by the Angelus the natural enemy of the Darkness. Also, Sara Pezzini, the host of the above Witchblade has appeared in crossovers.
- All Pegasus Knights in the Fire Emblem games are female; this is because the pegasi themselves won't allow men to pilot them. Wyverns, on the other hand, don't appear to be so picky, as there are Wyvern Riders of both sexes throughout the series.
- The Xbox 360 version of Rumble Roses appears to be this even though the game doesn't have a story. It's an all-female wrestling competition that also features mud-fights and photoshoots, and everything is devoted to Fanservice.
- The Heart of Candracar in W.I.T.C.H. allows a team of five Magical Girls to transform into Guardians to fight evil on Earth and in other universes. From what we've seen so far it's pretty much understood that only females are allowed to become Guardians for whatever reason, though the creator of the Heart was female in the comics and show and some fans speculate that this is the reason for the girls-only clause. The simpler explanation may be that W.I.T.C.H. is marketed as a girls' property and each of the Guardians are meant to relate to their audience.
- Later subverted in the comic with the Runics, a male Evil Counterpart of the group.