The specified term denotes a non-canonical pairing of characters from the Dragon Ball franchise: Android 21, a prominent antagonist introduced in Dragon Ball FighterZ, and Goku Black, an alternate version of Goku possessed by Zamasu. This pairing exists solely within the realm of fan-created content, such as fanfiction and fan art. It is a construct driven by audience imagination rather than originating from the series’ official narrative.
The popularity of character pairings, including the one in question, stems from various factors. These can include perceived character compatibility based on shared traits, contrasting personalities, or simply the visual appeal of the characters together. Such pairings are often explored for their potential narrative and emotional dynamics, providing a space for creators to express their interpretations of established characters and explore alternative storylines. The spread of such pairings is facilitated by online platforms dedicated to fan works, where audiences can discover and engage with these creations.