i know this is 4 years later, but I think they're all girls in this picture, Gosunkugi doesn't have long hair let alone a long braid, also that could be a serafuku shirt he/she has on, and that could be boob mounds, regardless I doubt the artist would have forgotten his normal all black uniform unless it was intended to be a genderswap for him, and Pantyhose is clearly not masculine given his normal appearance, does not include long lashes seen here or the feminine eyes.