Headcanon: Yamaguchi never hunts alone, only with other people. Most of the time, he tags along when Tsukishima goes out to hunt - and ends up partaking in his sadistic ways of killing. Another headcanon is that Tsukishima likes using different methods of luring their victims for fun.
A hooded figure darted past a lone man walking down the sidewalk, bumping shoulders in their haste. The man looked up in surprise before his brows furrowed into a scowl, muttering to himself about how people are always in such a rush in this city, even when it's midnight.
But upon taking another step forward, he found his pockets to be weightless - and a quick dig through its contents (or lack thereof) confirmed his suspicions.
"Hey, wait! Come back! That was my wallet, you punk!"
The hooded figure disappeared around the corner.
The man gave chase.
Panting heavily, he slowed to a stop once the person in front of him did as well - at the looming dead end of the pitch black alleyway.
"I've caught you. Now give me back my wallet."
Silence. The figure did not turn around.
"Can you hear me?"
More silence.
"Hey-"
A hand landed on his shoulder from behind.
He whirled around, fist swinging. Whoever was behind him ducked just in time, stumbling backward slightly.
"A-Ah… Sorry…" A timid voice.
He lowered his arm.
The stranger was just a kid; a teenager, probably, with wide eyes and a freckled face. The questioning thought of what someone his age was doing out this late did not cross his mind in that moment.
"Hey, kid. I'm a bit busy at the moment; someone nabbed my wallet. But maybe you could do me a favor and call the cops while I get it back…" He made a move to turn around when the kid's lips curved upward - letting a snicker escape. A prickling sensation crept up his arms then, but with the wallet on his mind - there was a lot of money in that thing! - his brain translated it into annoyance.
"Look, there isn't anything funny about this situation. If you don't want to help, that's fine, but I'll be going to get my w-"
"Yamaguchi, grab him."
He froze. The voice came from the figure standing at the dead end.
"Got it, Tsukki!"
Before he could wrap his mind around what was happening, he felt his arms being twisted behind his back. He let out a shout, attempting to wrench his arms free - but the teenager's grip only tightened and his limbs did not even budge. His blood flow oozed to a stop.
No way.
No way, no way - no way someone could be that strong. He trained in the gym, he lifted weights, he… he…
He heard a snap.
The pain registered a moment later.
He opened his mouth to scream, but nothing came out - for a hand was suddenly pressed against his mouth, clamping it shut and gripping his face so tightly his eyeballs bulged from their sockets. The stranger let go of his arms at once, letting them hang limply at his sides. When he dared to crane his neck around, in too much pain to dare scream again, his hazy vision caught sight of black sclera and red irises.
No… way…
"Sorry, Tsukki," came the same, small voice. "I broke his arms."
"Doesn't matter," said the figure, turning around and striding towards them as his hands tugged down his hood. "Besides, it's much more fun this way."
A red mist began to spread from his back, curling into the air, before four snake-like appendages burst free from within his flesh.
Even in the dim light, there was a faint glint along the rims of his glasses.
"Shall we eat?"
Tsukishima wiped the blood off the corners of his mouth, only to freeze when footsteps approached the alleyway. But when they rounded the bend, his muscles relaxed.
"Hmph, it's just you." His words were muffled by the sound of Yamaguchi hastily scrambling to his feet and crying out, "Sawamura-san!"
The black-haired man stopped in front of the corpse and stared down at it with a frown before speaking. "…You're eating too much, Tsukishima, Yamaguchi."
"Oh?"
"The CCG is going to crack down on us if we keep this up. We don't want another Oikawa on our hands."
"Heh." Tsukishima's lips curled into a sneer. "Wouldn't dream of becoming anything like that binge-eater." From behind him, Yamaguchi snickered.
"So you say. But this is the second time you've eaten in the past two weeks."
"Hmph."
For a long moment, the silence was breached only by the sound of chewing.
After some thought, Tsukishima tore off a forearm and flung it at his leader. "Here."
It landed with a wet plop against Sawamura's outstretched hand, smearing blood onto the skin of his palm - causing blackness spread across his sclera, pupils turning a vibrant red. Without a second thought, he tore at the flesh, crimson splattering across his face. Tsukishima smirked, but said nothing.
Tossing away the leftover bones and wiping the blood off his face, Sawamura heaved a deep breath and closed his eyes. When he opened them, his irises were a deep brown again.
"Are you done eating?"
Tsukishima narrowed his eyes.
"Well, I hope you are. There are some Karasuno ghouls who would appreciate the taste of fresh meat. The bodies we retrieve can sometimes be of poor quality."
"Tch. Then let them hunt for themselves."
"You're quite cruel, Tsukishima."
"And so is this world, isn't it?"
Sawamura let out a laugh, but it didn't quite reach his eyes.
-BONUS-
"Ah, so that's where you guys went! …Where'd you get all this money?"
"They stole it from the guy they ate."
"Eh? That's a bit mean, isn't it…?"
"Hmph. Doesn't matter; he's dead."
"…Still, it's a bit cruel, isn't it? Stealing someone's money and their life."
"…You're too soft, Suga-san."
"…I suppose so."