Diamonds and Stones

As I had predicted, the following Monday, our table looked less like the bunch of awkward misfit skaters and more like a group of arguing cats.
Naturally, Dan and Finn were throwing nasty glances at each other, Jack was trying to stay out of it, and I was sitting there, face-palming.
"Do you guys want to go to the skate park today?" I asked.
"Sure," Jack said, glad for the ease of tension.
Finn shrugged.
"I'm not going if he'll be there," Dan said.
"Guys, give it a break," I sighed, but immediately regretted it. They both turned to me.
"He stole my girlfriend!" Finn yelled.
"None of this would've happened if you hadn't run off with another girl!"
A poisonous silence engulfed us. No one spoke for several long moments.
"I never, ever, cheated."
His voice was deadly. The whole situation balanced on Dan's next move: either complete chaos, or toxic daggers of sentences.
"Oh yeah, Finn?" Dan said, his tone as lethal as Finn's. "Then where were you, hunh?"
"I was probably out back somewhere, but you didn't bother to look, did
you?"
"You were probably out back, making out with that Jessica chick and then puking your guts out. Oh but wait, you probably don't remember, you were so shitfaced."
"I was not. If you looked for me, you would've found me instead of doing my girlfriend!"
"Look, buddy, you seriously pissed her off. You were so drunk, you couldn't even recognise her. You 'mistook' that blonde chick for her. At least I had the decency to hear her out."
"What are you even sticking your nose into, Howell? You know nothing about Lizzy's and my relationship."
"Ex-relationship. She dumped your sorry ass before you could even register what was going on."
"That's not true. Anything that ended our relationship happened yesterday."
"I don't even know what relationship you're talking about! I didn't know commitment meant going around, making out with other girls in front of your girlfriend!"
"That's it," Finn said, standing up. Dan stood up as well. Jack shot me a nervous look and I just nodded, as if saying 'Follow my lead'.
I stood up as well.
"I don't know what game you're playing at, but you better stop it before I beat the shit out of you," Finn snarled.
"Oh yeah? Good luck trying, tough guy!"
"Enough!" I exclaimed. "You guys are fucking pathetic! What are you even doing?! I mean, for fuck's sake! You're both in the wrong! You, Finn, for not caring enough to prevent this, and you, Dan, for knowing fully well what you were doing! I don't even know the heck you're on about, but you messed up. Both of you. And look, my sister has to pay for your intelligence, or more so, lack of it. Now, you two sort yourselves out, kill each other for all that I care! Don't let me catch you arguing about how horrible your situation is when Lizzy is facing the consequences for your mistakes!"
With that, I picked up my bag, turned around and walked away. I heard footsteps behind me and assumed it was Jack, which it was. We were aware of the billion eyes on us, but we ignored them.
As we stepped out into the hallway, we sighed slightly.
"They're so..." I started, clenching my jaw.
"I don't know what to do," Jack said, rubbing his forehead.
"You must have it hard, too."
"Yeah. My twin or my best friend? As you said, they're both in the wrong..."
Suddenly, we heard the other door open and close, and footsteps running down the hall, away from us. We looked at each other. Hunh?
"Do you think that was someone we know?" Jack asked.
"Maybe. If we want to catch up to them, it's now."
We tore down the hallway, following the sound of the footsteps. They died down shortly afterwards, and we found ourselves in the hallway, in the area separating the girls bathroom and boys bathroom.
"Great, now what?" I said.
"Maybe it was nothing," Jack said. "No one we know, I mean."
"Yeah. Maybe."
"But now that we're here, I'll get my stuff from my locker."
"Okay, I'll just sit."
I sat on the floor, opposite Jack's locker. He opened it and was in the process of pulling his books out when the boys bathroom door swung open, to reveal a thin figure with jet black hair.
I blinked three times. The figure was slumping a little bit, trying to fix his hair and chewing on some gum.
"Phil..." I said, standing up.
He stared at me like a deer caught in headlights.
"Juliette... I- I can explain."