Many other characters exist, as well; Paul the ghost (who was, for a long period of time), the main protaginist of the series. Deceased as he was, and doomed to haunt earth as a ghost, he wore a sheet over him, to give him that "ghostly" look.
Jeremy was the antisocial roomate of Gary's, for some time, until he died. Then Paul haunted his body. So now he's Paul. Just so we're clear. If you see him on a strip, dont be all like 'HEY IT'S JEREMY". It's not. It's Paul.
There's a little girl called Maddy, daughter to Afsheen and Sara, and she is allergic to sunlight, so she often wears a pillowcase over her. She used to frequent the devil's tool, otherwise known as "the internet", but after being warned by Paul about the consequences, she has stopped. I guess. I don't know, I'm assuming that. Don't take my word for it. Go through 300 strips and figure it out for yourself.
Afsheen, and Sara. Together, a couple, the latter a cousin of Gary's. Allergic to metal and plastic, respectively. or the other way around. Not really sure.
The humor is mostly dark, and lacking a punchline, and reliable sources have confirmed that strips are often inspired by John's drug induced imagination.
Joking aside, it’s damn funny. You should check it out.