- Acting for Two: As with any animated series, you'll find some of this among the minor and one-off characters, but the most notable instance is Sean Hennigan; his main role is Decade, but he also plays the mob boss from November 11's introduction at the beginning of episode 5. This may have been a deliberate Casting Gag since the mob boss and his men are the first of November 11's victims we see, and Decade and his men are the last.
- Anime First: One of the rare double subversions: there actually was a Shoujo manga spinoff released before the Black Contractor anime (its first chapter was released in Monthly Asuka magazine on February 24, 2007, while the first episode was released on April 5, 2007).
- Fake Brit: November 11 is played by American Troy Baker in the English dub.
- Fan Nickname:
- Yin's Opposite-Sex Clone from the season 2 finale is often called "Yang".
- For Hei: Chinese Electric Batman, for pretty obvious reasons. In the second season, with the addition of Wild Hair and Perma-Stubble, he has been dubbed "Hobo Hei". Or "Heibo", if you're one of those informal types.
- For Suou: Mary Sueoh.
- For Mina Hazuki: Japanese Lesbian Catwoman, due to personality and style similarities to Hei and the fact that she's a Psycho Lesbian.
- Also, Lightsaber Lesbian.
- For Goran: Burger-kun or Russian Burger Flash.
- Meme Acknowledgment: Funimation is aware of the comparisons of Hei being Batman. Jason Liebrecht acknowledges the meme and mentions in a commentary for Psycho-Pass: The Movie that Hei's the closest thing to being Batman.
- Name's the Same: Hell's Gate did not appear due to Kayin Amoh's use of said special move.
- No Export for You: The Drama CD special was not released outside of Japan, and the Shikoku no Hana manga got outside releases only in French-speaking countries/territories.
- Playing Against Type:
- Nana Mizuki and Kate Oxley as Misaki Kirihara. Both women are known to play teenagers, young boys and girls. The latter was mentioned by several of the voice actors involved in several Darker than Black-related commentaries.
- Jerry Jewell for Kastinen. Zach Bolton mentions that he was happy to have this trope for him since he portrays teenagers and young men.
- Caitlin Glass as Alice Wang, who has an obsessive complex towards Misaki. She's known for voicing Winry Rockbell, Triela, and Cammy.
- Elise Baughman as Michiru. You may know her as Pan and Sayoko Shiranagatani.
- Pop Culture Urban Legends: Rumors have it that the show would have an OVA that centers on what happened during Heaven's War in Brazil. It never went through.
Trivia / Darker Than Black