Buffy was grateful that Bobby knew about the Slayer-gig. That meant he knew who he was dealing with now: someone who wouldn't give up, and who had a lot of power. If Dean and his brother were also into this kind of life, then they were probably skilled and powerful, too. However, the fact stood that she had super-human strength where they didn't. So with her on board, maybe they could change things.
"I...I don't know about hell hounds, or whoever this Lilith is..." she blinked rapidly. Research and lore - not her strong suit. "But I'd love the chance to deal with them," she said menacingly.
That was when Sam spoke up. Buffy tried to make herself stop from rolling her eyes. Of course this guy didn't know anything. He looked older than her, but his hair was all floppy and lame. Squaring her shoulders she faced Sam. "'Cause it is. ...a big deal." She cleared her throat, stepping forward. "There's only one girl in the world like me," oh God she sounded like Giles! "I have enhanced strength. Super-human strength," she added, figuring that phrase might register with him more. Looked like the comic book type. Him and Xander might get along.
"Strength, skill, a whopping array of multitasking abilities...and I can apply my makeup in under five minutes." A beat. "I'm talented." She was insulted by what Sam had said - obviously.
She needed to focus. "Listen, uh, I need to know whatever you know about hell hounds and this Lilith. Whatever the lore says about how you kill them - her, what repels them, anything like that. And then I'll need access to some of your weaponry, and a location." She sounded like a commanding military chief. But she just wanted to get this done. Trying to be nice, she said to Sam, "We'll get your brother back by tonight." She had to think like that - positively.
However, hell hounds and Lilith were big time, bigger than an average demon. She just didn't know that. It was going to be difficult it not impossible to kill them. Getting Dean back might be easier another way. Good luck trying to convince Buffy that!