Assuming I have no other obligations, I can totally spend the entire day on it. However, that doesn't really happen much with school, so drawing time has to come out of life functions time, like showers, eating, and sleep xD. That results to about a couple hours max, until I can't (or can't afford to) stay awake any more lol.
On the bright side, not eating means I finally lost my freshman 15 .
Kind of depends on what mood I'm in or how I'm feeling, but I can pretty much go all day at times just sitting and drawing in my sketchbook or sitting in front of my tablet. XD My dad gets pretty angry when I do, though. I get a bit antisocial. :U