ZaDR

Zim and Dib Romance is the slash ship between Zim and Dib from the Invader Zim fandom.

Canon
Dib and Zim are usually portrayed as mortal enemies, sometimes as rivals, and occasionally reluctant allies. As the series progresses, they both develop a grudging respect for the other. It is important to note that Dib, like Zim, does not know that Zim's mission is just something to keep him out of the way, and that he is a disgrace to the Irken population. Because he thinks Zim is actually a respected Irken, he is known to question how intelligent the species as a whole may be (i.e. "If Irkens are so advanced, why is your robot such a loser?").

However, it is interesting to note that they both need each other. Zim needs Dib to be motivated to finish his mission. Specifically in the unfinished episode "Mopiness of Doom", after Dib had given up on pursuing Zim, Zim simply stopped coming up with evil plans because he found it pointless. Likewise, Dib also needs Zim. Paranormal investigation is his passion, and Zim is the proof he needs in order for the world to take him seriously, otherwise they just think that he is insane. In Issue 1 of the comic series, when Zim disappeared, Dib became a complete shut-in refusing to even leave his room. He spent all of his time watching video feeds of Zim's house and places that Zim frequented, obsessed that one day that Zim would return. Both seem to be the only ones in the series who take the other seriously.

Additionaly, in the series there are friendship moments between Zim and Dib observed in several episodes:
 * Parent Teacher Night: Throughout the episode, Zim thinks about Dib, it can be said that only Dib tells him that he will have a bad day in the night of parents and teachers since Zim has no parents, but to the expectation of some fans, one could imagine that Zim thinks about Dib because he likes him.
 * Planet Jackers: Zim goes to Dib's house to get help from his telescope, although when he arrives at Dib's house, he is nervous to talk to his worst enemy in his home, although Gir gives Zim encouragement so that I can talk to him, then Zim, decided, goes with Dib, although this does not give him a good welcome, Zim tells him about the problem he has and Dib only defends himself with a lamp making Zim run. This is a ZaDr moment that fans like, since you can see that Zim is nervous or shy of talking to Dib.
 * Mopiness Of Doom (episode not issued by the cancellation of the series): This episode has never been seen by the cancellation of the series. However, in InvaderCON, the voice authors have made the episode to the fans, which deals that Dib leaves his study of the paranormal and studies Real Science as his father, making Zim come out victorious. Although he no longer had a nemesis to interrupt him in his invasion of Earth, he has no courage to do something evil without the presence of Dib, Dib for his part is proud to study Real Science with his father, as they became more united, although he still missed the program "Mysterious Mysteries" and his passion to paranormal things. This episode is considered a "Zim and Dib Romance episode", since there are many features between Dib and Zim distanced:
 * Zim feels sad and unable to do anything, since he could not see Dib lately.
 * Dib completely stops studying Real Science to be able to return with Zim.
 * GIR tries to convince Dib to return with Zim, because Zim took his chair, even nicknamed "Mary" as if it were a girl should return with her partner.
 * When Dib returns to be with Zim, Zim does not feel anger or hatred, but quite the contrary, he is happy to see Dib, and he even says: "You have no idea how happy I am to see you, little revolting larva".
 * When Dib and Zim return together, they start a battle, but it's a happy battle between the two of them, telling each other horrible things, but in a fun and cheesy way.

Fanon
Despite being rivals, many fans support Zim and Dib as a couple, nicknamed "Zim and Dib Romance". It should be noted that Invader Zim creator Jhonen Vasquez has stated that he strongly disapproves of Zim and Dib Romance.

InvaderCON is a fan convention organized by Green Mustard Entertainment, Inc. designed to be a 10th anniversary celebration for ''Invader Zim. ''It took place on March 26 and 27, 2011 in Atlanta, Georgia. Guests included Richard Horvitz, Rosearik Rikki Simons, Melissa Fahn, Andy Berman (Dib's voice actor), and Eric Trueheart. In the convention, Andy Berman was asked at InvaderCON 2011 to shout the words 'I LOVE YOU, ZIM!" for the Zim and Dib Romance fans. Additionally, the voice actors of Dib and Zim made their puppets kiss, which, an animation of a fan made this joke making posible.