To be fair the first time he appears in astral form he's posing as him.
Joel is the Antichrist
If you can't accept that he would really kill and/or ruin so many people just to get revenge on his brother.
Joel isn't really evil
He has just been corrupted by
his sister into getting revenge at all costs
Julian is the true villain of this comic
For all we know he'll make Joel look like a good guy.
Artie will turn out evil
He might have recently destroyed a small city and killed over 500 people, plus
Melusine has come back as a ghost and might be influencing him- Though who can really blame him after his girlfriend and unborn child were murdered by their own family in the name of the small city's laws, maybe due to Joel's manipulations.
Everything out of the norm didn't happen
The comic would make a lot more sense if it turns out all the rape and pregnancy and ghost sisters and murderous sea-mammals turns out to have all been a dream, and that it really WAS just a bunch of talking animals working at a wacky movie theater.
Lorelei will finally seduce Matt. Father Tim will be raped by Chelsie. Nicole will finally score Cecil. Thonnen and Naomi are descents of the Animal Christ. Lorelei, Joel, Miranda etc. are descents of Anti-Christ. Artie is incarnation of Krishna.
Matt is the one responsible for everything
He is clairvoyant and is changing the future in order to change himself, so he becomes more content after rejecting Jeremy.
Joel will lose control of his powers, plunging the world into darkness
All of Joel's efforts aren't actually to get revenge on his brother for killing Miranda.
What he's actually trying to do is create a bridge in space-time so he can cross over into the
Furthia High universe and have hot mansecks with Campy, it's totally true.
Joel started starving himself and later encouraging Matt to engage in S&M/body-mods with him to feed his sister's spirit.
It's confirmed that Miranda feeds on pain and suffering. The pain Joel feels while getting a tattoo/piercing/branding might hold her while he fits the next part of his plan together. Matt stopped Joel from starving himself, so he needed another method which Matt wouldn't stop, so he pretends it's merely experimentation and possibly psychically nudges Matt to be more open to it (though, if Matt's dreams in the guest strips are canon, he may not need to).
Joel is an unmedicated schizophrenic
Hate to point to
All Just a Dream, but what we seem to know for sure is when Joel was a child he spent a long amount of time in a psychiatric hospital where he was sexually abused by one of the caretakers. It's entirely possible when the comic begins and everything is more of a normal slice of life of working in a movie theater and going to college, Joel is still taking his medication.
However, eventually the world starts to fall apart, with Joel getting emotion-based shadow powers where he thinks people are out to get him, most of all his "evil" big brother who is some sort of psychic mastermind. At the end of the comic, however, Joel is finally forced to confront the reality because of Artie that his brother isn't some emo supervillain, he's just a normal guy who doesn't have any idea what Joel is talking about.
While it's easy to wave the comic off as being a furry emo superpower fantasy story, I think the fact the author spent so much time showing us how disturbed Joel is evidence that the comic is being told through Joel's perspective, and therefore we are dealing with a schizophrenic Unreliable Narrator who refuses to take his meds because he thinks the world is out to get him and if he hurts his friends in just the right way, he'll become a psychic super-god. This isn't to say nothing in the comic is happening, I believe Matt is in a relationship with Joel, but didn't "turn to the dark side" and gain superpowers, but is a bad and passive influence where he likes Joel off his meds.
