Some if not most of homestuck happens in space. And I've been bothered by this for a long while: how do they all breathe? Is it because they're immortal? But wouldn't they keep dying and then combing back to life?
Most of Homestuck takes place in a different dimension with a breathable outerspace. We’ve seen instances in normal outer space (like the incident with young Handmaid) where people still can’t breathe