He was never one for reason, let alone repentance. Zim and his outbursts, his minor disruptions of the waking world- not that it would be harmful in the long run, due to his impressive incompetence. But still, Dib needed a reason to exist, to get up in the morning and believe he was doing good for humanity. Even if the little pest would do very negligible, if any damage, it kept him alive, to think he was making an impact. In his own sad and unattended, unacknowledged life, it felt grand to feel important.
A year after the annoying little alien had arrived in his life, Gaz had enough of the nonsense and sat Dib down in a serious heart to heart, a record first- usually they kept themselves in bubbles, despite sitting in the same table at lunch. An expression bordering concern in her eyes, she frowned at him, voice with an even bitterness.
"Zim's an idiot, and you're an idiot for chasing him, because you know he never does anything that succeeds. If anything, your little fights do more damage than if you just leave him alone."
"But-"
"But nothing! I know you're starved for attention, and I know you want recognition, but set aside your selfish little crap and listen to me. Try ignoring him for a week. Trust me, you'll see the difference."
Dib, swallowing and breathing sharply, reluctantly followed her advice. Zim would exchange savage glances all throughout school, but he kept his word to his sister, not even looking him in the eyes, and outright ignoring him when he attempted to speak, brushing past those compact, deceptively frail shoulders and never giving him a sideways glance.
As much as he wanted to break this promised pattern, the week passed without incident, Zim's typical screaming eventually passing through his ears, a distant sound. The weeks piled up, and eventually became two months. He focused on his classes, kept limited eye contact, and spent time with his sister. After the initial almost-refusal went by, he began speaking to Gaz with brief snippets, which turned into paragraphs.
"What do you want to be when you're older?" he asked her, half thinking, and realized with sadness that they knew very little about each other.
"I want to design a better Gameslave interface, maybe learn to better code video games."
"I know nothing about that stuff," he admitted, curiosity slowly crawling in his mind.
"Well, it's best to start working for indie companies for basic interfaces and flash games for the web, and build a resume from your work. It's a hard career to get into, but I think I have the drive. People love escapism."
"Yeah, they do."
She laughed, a small sound that nearly went unnoticed. "And let me guess, you want to be a paranormal investigator and get recognized around the globe to have saved the world from an alien menace."
"You won't let me anymore," Dib said, and rubbed his temples. "I never really thought about it, to have a future outside of being recognized. But I do know that people suffer a lot. I really do want to save the world, I guess."
"You're right, people do suffer. And so do you." She stopped for a moment, as though to let the words sit in between them. "You don't pay attention though. You want Zim to not succeed, but there are worse things out there. Poverty, hunger, ignorance, really bad shit."
"...Maybe I should do something else then."
"You're on the right track."
The months grew longer, and soon enough Dib and Gaz spoke in solemn voices about their fears and aspirations, the boy feeling for the first time in his life, far from lonely.
Zim, however, had changed as well, with larger threats, and public displays of his machines and schemes. Gaz, in all her calmness, continuously repeated her request, and finally Dib understood.
"You know, he's almost like a girl who's flirting with you."
Gaz said this with utter seriousness, Dib raising his eyebrow at the statement.
"No Dib, seriously. He's trying to get your attention. And you're not giving it. Not to say he's in love with you, but doesn't it sound like it?"
"...You're right. Holy shit you're right. I almost feel bad for him now."
"You shouldn't."
"I shouldn't."
A year later, Dib took to volunteering in a soup kitchen, telling Gaz stories of shambling dirty people, and his decision to use his father's fame to spread out future humanitarian work. They remembered their birthdays, bought small gifts, and held each other dear. And Zim, growing increasingly desperate, took to shouting and violent tantrums, which Dib laughed at, feeling outright flattered at his strong emotions. To think, that he left that much of an impact on someone's life.
When Dib turned thirteen, Zim abruptly left the school, and his little house mysteriously disappeared from the empty parking lot.
"Wow... I don't know why I'm... I'm kind of sad."
Gaz shook her head. "He might come back, actually. And by then you'll both be prepared for it."
Zim read human books in a futile attempt to understand what Dib was doing to him, and why he felt so... what was it? Insulted? Hurt? Alone? The loneliness was what got to him, and Earth's boring sunsets and the coldness of people did not help his mood. Those books and stories, however, had at least aided him in adjusting his speech patterns, and inwardly he could swear he felt his bones shake at his increasing adjustment to humanity. He knew he was changing, and change made him furious.
What Dib did not see when Zim abruptly left without a speech or proper ceremony was time passing by, Zim's green skin adjusting to a pale olive color that was closer to human flesh, and earth's gravity granting him a boost in height, albeit 5'3" wasn't exactly flattering. Rain was still brutal, and so was the knowledge that no one gave two shits about him, except stupid Gir who grabbed at his head and noticed his grief. Cupcake offerings and little dances were far from reassuring, but at least he tried.
Knowledge was power, and armed with the knowledge that his superiors exiled him, he wandered aimlessly for what he perceived was a million lonely sunsets. He grew tired.
Experimenting with pointless camouflage led him to injecting himself with human blood, which managed to transform his body in something vaguely appropriate, requiring less use of the life support attached to his back, until he was able to function without it altogether. He ate human food, wandered aimlessly in homeless attire, and and one day checked himself into a shelter.
At the interview that checked his fabricated history and nonexistent drug abuse, he relished the softness of beds, and when going to the breakfast table with his fellow unfortunates, felt his transformed heart stop in mid-beat.
Dib served scrambled eggs and toast in a clean white shirt and a mundane haircut, and smiled at him, hair disheveled, face speaking of exhaustion. Clearly he didn't recognize him.
Zim closed his eyes and began to sob, and Dib approached him in concern, utterly confused.
"I'm sorry," The alien said quietly, eyes still vaguely purple, body emaciated and pathetically human. Dib opened his mouth, eyelids crinkling, and nodded.
"...I forgive you."