* FandomLifeCycle: Stage 6 A. The series has its fans but fanworks rarely get made and the fandom is disorganized. The fandom was most active in the early-to-mid 2000s.
* NoExportForYou: The [=PS2=] gaiden games aren't going to be released out of Asia. It only features a couple of characters, the cyborg Pia and her handler Earnest. They don't appear in the anime/manga version of ''Gunslinger Girl''.
* TheOtherDarrin: In an inversion of the norm, the second season and OVA feature a completely different Japanese voice cast, but retain the exact same English one with the exception of Hilshire.
* PlayingAgainstType:
** Rico in the first series is voiced by Creator/KanakoMitsuhashi... or let's say... [[Manga/HunterXHunter Killua Zoldyck?]] One Website/YouTube user who uploaded Rico's character song [[https://www.youtube.com/watch?v=ikzdoo_socg]] pointed this out and claimed, "It's really pretty. But if you imagine Killua or [[Manga/ThePrinceOfTennis Kouhei]] singing this, you'd probably choke."
** In the dub, Creator/LauraBailey, typically known for her more [[Manga/FullmetalAlchemist sultry]] or [[Manga/FruitsBasket energetic]] roles, spends much of the time speaking in a chilling near-whisper as Henrietta.
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