Just a head-up for the promo drop folks here. These servers are for communication/discussion, the members of these servers aren't big fans of people who come in to drop a promo then run, or try to spin conversations into promotions. While it's not against the rules, it's just not appreciated. If you join these servers please do so with the intent to be part of a community. (Or at least try to, I know sometimes a group just doesn't click or conversing can feel intimidating.)
I know of a few comic related server communities.
The Webcomics Garden - A super queer friendly, chill zone where you talk about comics, the comic process, OCs, stuff like that.
The Association of Comic Creators - A more serious server where publishers, pro comic creators, writers and indie folks come together to discuss and share info about financial stuff, conventions, experiences, etc. Webcomic and 18+ creator friendly.
Spiderforest - A server dedicated to the private collective, Spiderforest Webcomic Collective. While most of the server is collective members only there is a public section for anyone who is passionate about comics, the members there are also super nice and a couple of them also run the Webcomic Gardens server.