Qirl is a term for black transgender and/or non-binary individuals. It is similar to girl but is separate from the white/western gender binary. The name draws inspiration from African American Vernacular English (AAVE), as well as the fact that q looks like a backwards g.
The flag uses salmon pink, showing that it is similar to girl, which is associated with pink, but it is still its own separate thing. The three stripes in the middle are intentionally different from the middle stripes of the boi flag, showing that the two are not meant to be “opposites” of each other.