Abomasum

Oh, tough question. Harold individually was more entertaining, I'd call it, when he hated Andy. Although as a duo they were amusing as well, it just wasn't the Harold-ness itself that made it so great. So have to go with the spiteful Harry from season 1 - he was thoroughly amusing every single time he had something negative to say about Andy - and on a psychological level, I also found it extremely interesting how a grown man was reduced to behaving like a six-year-old in the presence of somebody who put his professional efforts to shame.

If one of these characters had to die prematurely, would you want it to be Harold or Andy?