- Fandom Life Cycle: 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.
- No Export for You: 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.
- The Other Darrin: 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.
- Playing Against Type:
- Rico in the first series is voiced by Kanako Mitsuhashi... or let's say... Killua Zoldyck? One YouTube user who uploaded Rico's character song  pointed this out and claimed, "It's really pretty. But if you imagine Killua or Kouhei singing this, you'd probably choke."
- In the dub, Laura Bailey, typically known for her more sultry or energetic roles, spends much of the time speaking in a chilling near-whisper as Henrietta.
- Relationship Voice Actor: Henreitta and Triela are voiced by Laura Bailey and Caitlin Glass in English dub. Therefore, they're Shin-Chan and Miss Anderson, Kanako Kasugazaki and Haruhi Fujioka, and finally Chun-Li and Cammy.
Trivia / Gunslinger Girl