It was another typical evening in the Membrane household. The professor was out, presumably saving the world from some clandestine catastrophe, Gaz was draped over the living room chair, glued to her aptly named Game Slave and Dib was stretched out on the couch, remote control in hand and watching the newest episode of Mysterious Mysteries. There was a special on vampires developing a new high-factor sunscreen which allowed them to travel outside during the day.

Dib was 16 now and much the same besides his impressive height. He had shot up like a weed over the last few years, developing a gangly frame allowing him to tower over his nemesis, Zim, which of course served to infuriate the Irken and provide the teenager with endless amusement. Zim himself had grown due to the earth's differing gravity, Dib had theorized, but only a little, the tips of his antennae only reaching the human's clavicle.

It was summer vacation from skool which allowed Dib plenty of time to monitor Zim's activities, but tonight was his night off and he was content to let the other plot his next failed attempt at conquering earth. Yet still he found himself pondering over the curious invader.

As if in response to his wandering thoughts, the front door burst open, slamming off the wall with such force a vase on a nearby table fell and shattered. Dib sat up instantly to see the intruder while Gaz didn't so much as glance up from her game. The boy's jaw fell open at the figure in the doorway – Zim in his hastily applied disguise, covered in scorch marks, some still smoking, clutching what appeared to be an Irken duffle bag. Zim marched purposefully through the living room without acknowledging the gawking human and ascended the stairs. After a few stunned moments, Dib managed to turn to his oblivious sister and said, "Gaz, did you see that? Zim just broke into our house!"

Gaz grunted irritably and said, "If you distract me from this boss my fist will break into your face." Dib ignored the threat and pursued the alien upstairs, his mind racing. What was he doing here? Was this some new scheme Dib wasn't aware of? He should have been monitoring him, he should have been ready! He followed the scent of smouldering material to his room. He walked in to see Zim set his bag down on the bed.

"Zim!" he shouted, anger replacing surprise. "What do you think you're doing? You can't just walk into my house like you own it." Zim turned on him, ripping off his laughable disguise in the process and tossing the singed wig and contacts to the side, revealing his antennae and his crimson eyes full of malice.

"Why I'm here is none of your business, Earth monkey."

"This is my room in my house, so I'd say it is my business," Dib said, his hands clenching into fists, ready for a fight. But instead of an attack, Zim merely sighed angrily and sat down on the bed next to his bag.

"My base is..." he began, unsure of explaining anything to his mortal enemy. "Unavailable," he managed, voice dripping with venom. Just then his luggage erupted and out jumped his hyperactive little robot.

"I made waffles! Computer sure was huuuuungryyyyy," cooed the faulty SIR unit.

"GIR!" Zim jumped back and shouted. "I deactivated you, how did you get into my bag!" GIR had already gotten down from the bed, found Zim's wig and began prancing around in it.

"I got bored," the robot offered giddily.

"You...got bored of being deactivated?" asked Zim in disbelief and GIR hummed a little 'mmm-hmmm' while posing in front of Dib's mirror. The Irken's face darkened with rage as he got up, walked over to the robot and ripped out its eyes. Dib watched in horror as he carried them to the window, opened it and flung them into the night.

GIR stumbled, regained his footing, felt around his empty sockets before screaming "I love this game!" and launching himself out of the window to hunt blindly for his eyes, dropping Zim's wig as he did so. The seething alien returned to the bed and sat down.

Dib was dumbstruck for a moment before asking, "He made waffles?"

"And jammed them into every opening in the equipment in my lab," Zim replied, fury giving way to weariness. "So much syrup," he said absently and shuddered. "Once I managed to get the computer functioning I initialized a clean-up program for the base. The damage was more extensive than I thought and I had to vacate until the process is complete."

Dib allowed this all to sink in before asking, "And you think you can stay here while your base cleans itself!"

"Yes," Zim said simply and lay back on the bed while rubbing where the bridge of a nose would be between his eyes – a habit he had unconsciously picked up from the humans.

"Well, you can't! What makes you think you can move in unannounced? If you haven't noticed, we're enemies."

"Because this is all your fault." Zim said coolly, not even looking at the other.

"My fault!" Dib shouted, incredulous.

"Yes," said the Irken, sitting up and looking at Dib. "If you would have just let me conquer this dirt ball years ago I wouldn't still be here and I would have a functioning SIR unit who wouldn't force-feed my computer waffles until it exploded, Dib-Stink."

"That's stupid," Dib said, low and angry, "now get out of my house."

"Make me, worm," Zim challenged as he stood, spindly mechanical legs protruding from his PAK and lifting him off the floor until he was a good few feet above Dib, more than making up for the height difference. Dib shuffled back defensively and considered his options.

"I can call the cops, you know," the human threatened meekly. Zim laughed and his amusement diffused his aggression enough for the legs to retract.

"After all these years of the humans mocking you," he said, still laughing, "do you really think they'll believe you now?" As much as Dib hated to admit it, he was right. He could just put on his human guise once more and the cops would most likely charge the "crazy kid" with another false alarm.

"I still have contacts in the Swollen Eyeball," Dib said, still trying to sound threatening despite his dwindling options. "One whiff of alien activity and you'll be in a test tube before sunup." Zim reached into his bag calmly and retrieved a slim black device with a faintly blinking red light.

"This device blocks all electronic communication within a set distance," he explained, smirk plastered upon his face. "A pointless gesture considering nobody will ever take you seriously, but we Irkens never leave anything to chance." Dib was at a loss for words which only amused Zim further. "Face it, Dib, you are alone. You may as well bask in my presence until I can return to my lab and enslave your pathetic race once and for all." Dib considered using his family as a threat to Zim's cover, but they cared just as much as everyone else about his extraterrestrial claims. It looked like he didn't have much of a choice.

"Fine, Zim," he finally submitted, "you can stay." Zim's face was so smug he could have hit the green boy, but he wouldn't risk the resulting fight destroying his home. "So, how long will it take for you base to become operational?"

"3 Earth days," Zim answered, unpacking as he did so. He pulled out a spare uniform and what appeared to be a laptop, though Dib wasn't yet familiar enough with Irken technology to be sure.

"So, where are you going to, uh, not sleep?" Dib asked at length, remembering Zim's species didn't need to rest like humans. The green boy flipped his equipment open which unfolded into several screens and keyboards. The Irken alphabet must be more extensive than the English one, Dib idly wondered.

"Here," said, his face already illuminated in the light coming from the screens.

"My room?"

"Yes. Unless you want me setting up downstairs for everyone to see."

"Point taken," Dib said tiredly. "But I better not catch you going through my stuff."

"I already know everything I need to know about you," Zim said with a grunt of laughter. "Really, Dib-Stink, Irken technology is vastly more advanced than anything your doomed race has come up with. You cannot comprehend the immensity of our brain meats."

"Oh really," said Dib, indignant as he moved to sit beside the alien boy on the bed. "And what exactly do you know about me?"

"You are more than capable with human technology, adaptive to alien language and systems, though lacking in physical strength you are not entirely useless in combat," Zim recited as though reading from a list. It seemed the night's surprises were still coming for Dib, as he listened to his traits in what almost sounded like praise. Zim continued: "Your father is Earth's top scientific mind which gives you access to government sectors and top-secret developments. Your favourite colour is blue. You are near-sighted. Your mother died when you were three years old due to-"

"Whoa, whoa, whoa!" Dib yelled, jumping from the bed in agitated confusion. "Favourite colour? My mom? That's valuable enemy intel?" Zim stopped what he was doing and looked at the boy with a smirk; pleased that he was able to rattle him with his brilliance.

"Psychology; humans can be affected by something as trivial as colour. Your pitiful connection to parental units is a weakness, easily exploited," Zim explained, his dangerous looking teeth revealed as his sinister smile widened. "I know you, Dib...unpleasant as it is." Dib approached the other, and leaned down until they were face to face, closing Zim's computer as he did so.

"Never, ever, mention my mom again."

"See?" Zim asked, still smiling and leaning back on his hands. "Weakness," he hissed and they stared each other down for seconds which felt like minutes. Finally, Dib stood up and stormed out of the room. Meanwhile, Zim opened his equipment and got back to work.