Lyric discussion by Sharp 

Cover art for Pet Name lyrics by They Might Be Giants

I agree on a few points, but I think that she did like him. It seems like she's a girl who tries to put up a tough atmosphere, but deep inside fell in love with the speaker. Her mouth says no, but her heart says yes. Eventually the singer ends the relationship out of pity for the girl, and sadly sees her go back to her isolationist attitude.