Xander watched as Buffy and Angel walked towards the dance floor, and the band began to play a slow song. Angel twirled Buffy, and Xander stood, glued to the spot, wishing that was him up there with Buffy, instead of Angel. But it wasn't. Eventually, the wish became too strong. It overpowered him. He wanted to dust Angel. How would he do that? With a little help. He watched Buffy spin round one more time, making sure to catch her eye, before he left. Willow watched this, and figured something was up. Buffy also saw Xander leave.
"Xander! Xander, wait!" Willow called, running after Xander. "Xander! Where are you going?"
"To get help."
"Help? Help with what?"
"That's none of your business."
"Don't do anything stupid!"
"And what would you describe as stupid?" He turned on her. "Me? My obsession with Buffy?"
"No… Don't do anything stupid, as in don't go out and get yourself killed because you can't stand to see Buffy dancing with the one person she actually likes!" This outburst from Willow made Xander stop dead in his tracks.
"The 'one' person she actually likes?"
"It's true. I know you more than anyone, and if you love her as much as you say you do, you wouldn't go and do whatever it is you're about to do."
"Do you remember when Amy id that love spell for me? The one that was meant for Cordy? The one that went terribly worng? When you tried to Axe-Murder me? This is like that, only it's not a spell. It's real. I remember you saying to Buffy once, while Giles and Me were digging up an empty coffin in the grave yard. (Yes, I heard you two talking that night.) You said 'Love makes you do the whacky'. So this is it. This is love making me do the whacky. And there's nothing you can do to stop me."
"So…" Willow chose her words carefully. "What are you going to do?"
"I'm going to dust Angelus. The monster."