Hugo is the school's creepy security guard. I'm not sure if it's just all the drugs Hugo took in his younger days, or if it's just working both the day shift and the night shift, but he's a tweaker.
I'm not quite sure why they have a security guard at that high school though...the only thing kids have to worry about there is Tim and Travis, and Hugo doesn't seem to be caring too much about their extracurricular activities. But, I guess for show purposes he should stay on, 'cas without him, the show just wouldn't be the same.