Headcanon: Iwaizumi has a lot of human friends. While Oikawa also mingles with humans, he does so professionally as a model. Another headcanon is that Trashkawa likes eating his fangirls, although he can't do it too often or else suspicion might arise.

The sound of coughing and hacking and retching filled the alleyway.

Breathing heavily, Iwaizumi wiped his mouth with his sleeve after he had emptied his stomach of the disgusting food. From behind him, he a familiar peal of laughter, and fought the urge to whirl around and punch him.

"Oikawa… Leave me alone."

"What? I didn't do anything."

More heavy breathing.

"Well, your stomach must be pretty empty now… How about we find some food later?"

Iwaizumi glared. "No."

"Eh? Aww, why not?"

"You already ate."

"But that was a week ago, Iwa-chan!"

"Don't call me that. And you've gotta stop doing that!"

"Why?"

There was that glint again, in his eyes.

"God damn it! You're endangering all of us, you know?!" Ignoring the sifting of his unsettled stomach, Iwaizumi spun around and stalked up to Oikawa. "You and your fucking binge-eating habits! You're on the top of CCG's hit list. They're gonna find us sooner or later. And all because you like seeing people die."

"By the hands of my super cool kagune," Oikawa finished with a grin - and neatly blocked Iwaizumi's punch with his arm.

They stared one another down.

"You know," the brunet sighed, "you're getting too attached to your human friends."

"Is that why you're mad, Iwa-chan?"

"Hell no!"

"Hey, your kakugan came out."

Iwaizumi blinked, shook his head a few times, feeling his vision swim. But his eyes did not return to their original color. Instead…

Shit.

"…Iwa-chan, when was the last time you ate?"

"…Shut up." His voice came out raspy and choked.

"No, really."

"…three months ago."

Oikawa's smile disappeared.

Iwaizumi glared - or tried his best to, for the scent of fresh and alive human beings was rapidly overwhelming his senses.

"Fine," Oikawa stated, his voice without a trace of mirth. "I won't eat today."

Black and red eyes narrowed, waiting for the rest.

"But, you on the other hand… are going to eat. If you can't hunt for yourself…"

"No!" Iwaizumi spat out as his stomach rumbled. "I'll do it myself."

He straightened up, placing a hand to his forehead and heaving a deep breath. "I've had enough of your bullshit. Let me do it; I've been hunting the least out of everyone here. If they're gonna catch me, it's not gonna be today."

The smile was back on Oikawa's face.

"Yay!" he said, clapping his hands. "Have fun!"

Iwaizumi grunted unappreciatively.

"Oh, and here!"

A mask hurtled towards him. Iwaizumi snatched it mid-air, placing it over his face with a snort before marching off.

"And before you go, Iwa-chan?"

He stopped. Turned around to see Oikawa still smiling, but without any of it in his eyes.

"Remember that I'm the leader, not you. You don't have to shoulder my burden alone."

"Tch."

-BONUS-

"Ahh~ I feel kinda bad for his victim. Iwa-chan's not very scary when he's mad, but when he's hungry…" Oikawa grinned. "Heh~ Maybe I'll go watch!"
"You're quite sadistic, leader-san."
"Oh, really? Hey, Akira - do you think he'll let me share?"