Need Some Help With Introducing Another Main Character?

[BambiiGirlHottie]

ok so, i would love some help guys!
in my story I'm currently writing, I'm up to introducing the character that is soon to be her love interest. No matter what i write i can't seem to get the tone set properly.
His name is Logan Bromwell, 18 years old and a complete bad boy who's just got out of a fight.
A quick summary of the scene is basically my main character, Ryan is walking to her car at night and sees a group of guys beating this one guy up. She wants to help but doesn't know how.
this is the very basic dialogue, no added details no nice writing. I'm going to write the speaking in the simpliest form but i just want it here so you guys can read it and get a feel for it so don't comment saying it's crap because i'm missing out details, actions, thinking everything. This is just dialogue!

WARNING! HEAVY SWEARING!!


Logan: “F*ck off!â€
Hooded figure who's hitting him. “You owe us!â€
Logan “I don’t owe you anything!â€
Hooded figure: "You dogged us! Gave us the sh*t weed!â€
Logan: “I don’t do that sh*t anymore! I didn’t dog anyone! You were the ones that asked for a f*ckin’ dealer! I gave you a name!"
2nd hooded figure: "Oi, look." (the hooded figures turn to see Ryan) Do you think she’ll keep walking?â€
1st Hooded figurer: “Shut up, would you? I don’t give a sh*t about her. I’m gonna finish off this f*ggot.†(after logan gets hit a few times more, police sirens sound but its for a party lower down the road. the hooded guys run off and Ryan walks over to Logan. He stands up and they realise that they know each other from Highs School but he dropped out when he was 15 years old.)

this is where i have no idea how to make them interact with each other. I want Logan to sound cocky and up himself while Ryan to be kind of like 'ugh, just my luck. What do i do now?'. I don't want her to just walk off because later on in the story it's going to be revealed that her best friend was gay and got bashed to death with her there watching so she refuses to walk off on people after a fight.

Please help me guys? i have no idea what i want them to say to each other. this is te Dialogue i have right now but i don't think it's working very well. also, here's what i've written to introduce him but it's heavily lacking in every aspect.

“Hey, are you ok?†I stood up when the guy got on his knees and pushed himself up, holding his ribs. And then I took a few steps back as I realised it wasn’t just his voice that was familiar. It was everything about him. His eyes, hair, body. Everything. “Holy sh*t.†I whispered sighing. This wasn’t going to be good.
“Ryan?†He asked, smirking at me with his bad boy demeanour. God, he looked smug. That bastard. The smirk he had plastered on his face was as if I’d done something extremely sexy for him, which I hadn’t. All I had done was walk over and ask if he was ok. He stood up straight and wiped some blood from his lip. I saw the blood was dripping from his lip and his nose was leaking the smallest amount. He didn’t look too badly damaged though. “Shouldn’t you be leaving? Y’know, underage drinking and all that.â€
“I’m the deso tonight.†I said coughing once. What was I supposed to do now? “So, you alright?â€
“This?†He asked shrugging. “I’ve had worse.†Of course he has. Meet Logan Bromwell, the typical bad boy from High School that seemed to emit trouble with everything he does. Except, he dropped out of High School in year 8 for some reason. After that rumours went around that he’d been sent to jail and not for one second did I actually think it was false. “This is just a scratch.†Yeah, of course. I thought. Busted up lip, bleeding nose, cut cheek. Thats just a scratch, huh? Logan turned his back on me and started to walk off, but I didn't want him to. I couldn't just leave him to walk off alone after a fight. Not after...not after Mikey.
"Hey, wait!"


PLEASE HELP!!
I really can't get the feel across in this scene. Nothing i type really shows how dangerous Logan is and how dominant his presence is.
Please help me out guys!