Though further details regarding the exact type of non-binary identity the new character will have is yet to be known, the issue will be dealing with the struggles of being a young non-binary person who is trying to gain acceptance. Here is the description for the new comic:
In his search to write a CatCo piece on the truth about Supergirl, Ben Rubel interviews a young kid named Lee Serano, who recently became friends with the Girl of Steel. As Lee struggles with their parents and bullies at school for acceptance as non-binary, Supergirl is caught between punching her way through the problem and standing beside Lee as a symbol of hope.
It remains to be seen whether Lee Serano will have any special powers, but the character appears to be flying on the issue’s cover. Serano is not the first non-binary character to appear in the comic book universe, however because the Supergirl series has a reach ranging from tens to hundreds of thousands of readers, it is largely being seen as a significant step forward for non-binary representation in comics. Some other comics to have featured non-binary characters include Desire from Neil Gaiman’s Sandman, Rebis from Grant Morrison’s Doom Patrol, and Xavin in Brian K. Vaughan’s Runaways.
Supergirl (#19) by DC Comics was written by Steve Orlando and writer Vita Ayala, who identifies as non-binary. It features artwork by Jamal Campbell and a cover by Horge Jimenez. There will also be a variant cover created by Stanley “Artgerm” Lau.
The 32-page issue of Supergirl (#19) goes on sale March 14th, 2018.