Zim knew what he had to do. Since Zenn was dead, he knew she wanted him to love Gaz, because she loved him. So,
"Gaz, I-" "Hold on. I have to ask you something. You know how Irkens have paks? Well if an Irken dies and you put their pak back on, will they be alive again?" "No, but there is one way. But it's on Irk and I'm banned. So it's no use. None at all." "So what were you saying?" "Gaz I know that I love Zenn but I think that now that she's gone that she wants me to love her best friend. She told me that was you. So, I love you."
Then Zenn's spirit came back. "Thank you Zim, I knew you would do that for me. I love you. Bye."
"Really, you love me!" "Yeah" "Oh Zim, I know you are sad, but Zenn's spirit will always be with us. She'll make sure we are okay. So let's be happy and get on with our lives. Okay?" "Okay." He gave her a kiss on her cheek and turned the TV back on the Scary Monkey Show.