down in the park

Harry, Mark, John and some of their "friends" are sitting down in the park. You know the place, those trees, near some pond or something. Somebody brought a guitar. Must have been Mark, since he's playing now. Lousily. Two or three chords. Over and over again. He just varies the picking, does some bending now and then. Stuff you would do if you wanted to impress someone who doesn't know much bout playing guitars -- or music in general, for that matter. While Mark is strumming, picking, bending and sliding on or along the strings and Harry leafing through some book somebody took along, John starts talking. He breaks the silence that has filled the stale summer air between them.
"Ever considered starting a band?"
Mark replies: "Dude, forgot how we met?" -- and adds (after a pause, short enough not to be recognized): "I'm definitely over that band stuff."
Harry puts down the book, looking annoyed, as if he was disturbed while doing something of vital importance. Before he opens his mouth to complain in a manner completely inappropriate in the situation, he takes a look around --and changes his mind about what to say. "Guys, have you notice that we're alone?"
Mark and John turn their heads... He's right. Where have they gone? When did they leave? Why didn't they... Questions like those cross their minds.
Mark manages to say: "When did... uh... Sally, whatshername, and that other guy leave?"
Harry: "... I don't know... -- by the way: who was he? Seemed kinda weird to me."
Mark: "You're right-- he was so... oblivious. I can't stand that."
John: "Guys... what about the band?"