It's a name for the comicsgaters, but in this case it's specifically a guy who roams Captain Marvel/Star threads and anything related to it (specially female costume threads) and always posts the same kinda shit. Like this post for example >>112490941
, or this one >>112487020
, but it's more apparent here >>112495647
. It's easier to recognize when you decide to question the practicality of leotards for female costumes, because he then dumps his folder of gymnasts and claims superheroines look good because they do, like clockwork.
He also tends to fly under the radar because criticizing skimpy costumes gets associated with sjw nonsense, even though the criticism stems from how generic they look, not the sex appeal factor of it. But the guy is obsessed about it.