Darker than Black (TV)

Hei`s name means (black), Yin`s name means (silver), Huang`s name means (yellow) and Mao`s name means (cat) in Chinese.

Hei's apartment number is 201, just as his star ID is BK201.

The text in the book(s) Luco is reading in episodes 3 and 4 is from "Anne of Green Gables", although the covers of the books seem to be something else.

There are two Coca Cola sign on top of Yin's house/shop.

In episode 7, the restaurant below Kurasawa Gai`s office was (Pizza Hut).

In episode 13, Kiko got furious of someone, so she said that she would kill him by writing his name in her notebook. That is refering to (Death Note) anime.

In episode 13, when Detective Gai is looking for Yin at the shop and Mao hides from him, there is a scene where you see Li (Hei) looking at a cat on a fence. This cat is probably the one that Gai was looking for in episode 8 (Miiki).

In episode 19, after Hei has infiltrated the religious group, he is asked by his contact to read a certain passage. The page number is 201 again, just like his messier code (BK201).

In episode 24, when Amagiri and Brita (members of the Evening Primrose) go to PANDORA to destroy the particle accelerator, they are attacked by a Contractor who uses a powerful fire attack on them. This Contractor is most likely Mai Kashiwagi, the Moratorium girl who turned into a Contractor in episodes 3-4 who was taken away by The Syndicate.