Unluckily for Dib, the new guy in the solar system had taken some weird liking to him. Zim, and sometimes Gir too, would follow him like a lost puppy dog. He eventually got used to it though... After all, Zim was very honest about the Irkens and he did kind of like learning about them
After a while, though, Zim managed to surprise him again. They were hanging out at Zim's house, just talking, and Zim suddenly jumped on him whenever he mentioned relationships. "That reminds me! What's this 'kissing' thing I've heard about?" He asks, causing Dib to blush.