Lyric discussion by infotainment_lad 

Cover art for Mouth Breather lyrics by Jesus Lizard, The

I always assumed a 'Mouth Breather' was just supposed to be someone who's stupid, they're not smart enough to breathe through their nose. So I figured this song was supposed to be about how he likes the friend, he's just an idiot for taking the drugs (and overdosing while looking after his house etc etc).