Alright! In defence of my fourth favourite cat after my own three, sorry my fifth including Goldy from this forum, I see him as the fun friend Lister turns to when Rimmer gets too much. The friend who allows Lister to be himself without constant haranguement (I don't think that's a real word). Perhaps, in some ways, like Holly he became redundant after the introduction of Kryten. But I still think of them as best buddies. And I think Lister would have gone space crazy without him.