"Bishoujo" simply means "pretty girl" in Japanese.
A bishoujo series, however, is a more loaded term. They are Fanservice series aimed towards male audiences. These series will use highly attractive female characters (often of The Beautiful Elite variety, although this is not necessary) up to about twenty-five years old whenever possible. This is especially noticeable in a series where male characters and older women make unusually few to no appearances, even if the story's setting and premise would suggest otherwise.
Lately, among fans, it often takes a self-derogatory tone. Many bishoujo series blatantly appeal to male audiences with pandering tropes, causing large amounts of Values Dissonance that help cement the otaku stereotype. Adding a guy to the mix ironically just gets it labeled as a Harem Genre story.
When a series of this kind does attract Fangirls, the series often loses this term. Compare and contrast Shōjo (Demographic) and Magical Girl, in which there are cute girls, but the target audience is female. Also contrast Puni Plush, Gonk, Hunk, Bishōnen.
This is an East Asian media only trope. Please do not put Western examples here.
- ARIA, where only beautiful young girls appear to be allowed to steer sight-seeing gondolas.
- Pretty much every girl in Elfen Lied, Diclonius and human alike, is very beautiful. Because of this, the opening scene is particularly memorable, what with Lucy going on a killing spree while wearing nothing but a mask.
- Naturally sent up in Excel Saga, which featured a bishoujo episode in which the art became noticeably more shiny and all of the male regulars except Pedro were deliberately excluded. Pedro's Big "NO!" comes when the male cast finally comes to exact punishment for his appearance — and we still don't get a good look at any of them.
- Galaxy Angel is a bishoujo series; the Galaxy Angel gameverse has the same characters as a Harem Genre, but the anime removes the central male.
- Gunslinger Girl has an especially jarring dichotomy between the age of the girls in question and their occupation.
- I'm Gonna Be an Angel!.
- KoihimeMusou is notable for its sheer volume of bishoujo. There are literally dozens of all shapes and sizes.
- Str.A.In.: Strategic Armored Infantry.
- Strawberry Panic! is a Yuri Genre example.
- Strike Witches.
- To Love-Ru.
- Parodied in Anime-Gataris, where the entire anime club (including Neko-sensei) inexplicably becomes full of cute girls thanks to the Reality Bleed of 2D tropes into real life.
- Arcana Heart
- Rumble Roses
- Dead or Alive Beach Volleyball, complete with revolutionary Jiggle Physics.
- Final Fantasy X-2.
- Vanguard Princess
- Tokidensho Angel Eyes
- Neptunia is nothing but this.
- Getter Love!!
- Touhou. An astounding grand total of two males appear in the official works, and one of them is a magical cloud. The females? About 80+ of them, not counting pre-Windows versions.
- Kantai Collection was intentionally designed like this, but then it suddenly got popular, getting the non-otakus and many female players mixed in as well. At its heart, however, it is still a bishoujo series franchise.
- Katawa Shoujo. A Visual Novel made by an international team in the style of a Japanese Dating Sim. This fact gets lampshaded in-game too.