Though The 13 Voices all protect The Ageless Black, they're individuals and as such, have their own likes and dislikes and so have broken off into their own groups of friends (or "friends" as a particular duo puts it). These groups have become so concrete, that others have given them names. The Quartet is the "main group" since it consist of the "leader" Twist Tie.

Note 1: Voices are technically genderless, but for ease of communication, genders have been assigned to them. Use of they/them is also acceptable.
Not 2: Even though The Voices all come from the same source, they don't see each other as related to each other in a familial sense but simply pieces of a bigger whole, so while a Voice may be described as "sisterly" or like a "big brother," this is for descriptive purposes only.

old Bun Life comic from 2015

It's pony time with this commission for NovaSquirrel from 2021