I would guess that's about it: lack of women = misogyny. I mean, I don't know the comic, but if there are only a handful of characters being focused on, throwing a token woman in there just seems...rude? Webcomics cater a lot to author appeal, so if the author is only interested in (gay) men, then that's what the comic is going to be about. Maybe they simply don't feel comfortable writing female characters, because there's a lot of "damned if you do, damned if you don't" attitude regarding it. IMO, so long as there isn't an unreasonable dearth of female characters or disproportionate negativity towards females, I'm not really seeing misogyny.