Disclaimer: Buffy the Vampire Slayer and co. belong to Josh Whedon and other people who aren't me.
Summary: Spike attacks Buffy while on patrol and Dawn knows It's time to do as she promised
Timeline: Set in early season seven.
No one knew that Dawn was awake when the got home, if they had they wouldn't have said everything that they had. Dawn heard it all though, she heard how Xander had found Spike attacking Buffy, how once again it was the white knight to the rescue. Dawn didn't know why Spike had attacked Buffy but to put it bluntly she didn't give a flying fuck.
All that mattered was that Buffy was laying bloody and broken hurt beyond belief. The only thing that mattered was her anger; her rage was like a cold fire burning deep within her, she had made her plans for this long ago. Sneaking back upstairs she collect her gear and left for the school.
Dawn was sitting on her bed crying, as usual Spike was at her side hold her his tears mixed with Dawn's. It seemed like every night they ended up in the same place, both of them too much in shock over Buffy's death to be any good. Together though they were finding they're way through the long dark night of grief.
During the day Spike would sleep on her floor while Dawn sat on her bed watching the vampire, to everyone else's surprise they were lost without each other. Every waking moment was spent with each other, while everyone else held the demonic forces at bay the two of them held each other together.
//It was all a lie, everything he did was a lie.// As Dawn walked towards the school people crossed the street to avoid her, if she had been paying attention she would have seen two vampires flee in terror from her. She wasn't paying attention though all of her energy was focused at the problem in hand, the extermination of her enemy.
When Xander had been gung ho about killing Angelus he had explained it to Dawn, after all she was the only one willing to listen to her. The way Xander explain it seemed harsh to Dawn, until now. Xander had said that Angel had been a heavy hitter for the Scoobies, but as Angelus at best he was a liability, at worst a threat that could tear them apart.
Dawn understood, Spike may not be able to hurt them all but he could hurt Buffy. Like Xander that was enough for Dawn. Anyone who hurt Buffy; hurt her as well and that was enough for Dawn. So Dawn went upstairs and got her gear together; her plans had been made long before she had voiced her promise.
When Dawn got to the school she used the key her sister had given her and punched in the security code. When Dawn got to the basement she stopped and took off her backpack, within seconds she had the tranc rifle assembled and ready. //Xander's training is finally paying off//
Dawn slowly made her way through the basement, even though she didn't know the exact lay out of the school Spike general stayed near the hell mouth. It wasn't long before she heard Spike inane rambling, before it had invoked pity now all it did was anger her. //Stupid shit, you'll see what happens when you fuck with the Summers//
Lifting the rifle to her shoulder she shot the dart the way Xander had taught her, almost instantly Spike fell to the ground unconscious. Half an hour later Dawn was dragging his limp chained form out of the school. It took her hours to set it all up; when she was done Spike was chained to four posts in her back yard stretching him face up. Minutes after she finished Spike finally woke up, the realization of what Dawn was doing seems to partially return his sanity.
So he started begging, pleading for his unlife; Dawn just smiled a cold hard smiled and watched him. When Dawn sees the coming of the sun she turned and walked towards the house, she wanted him alone when he was dusted. "I told you that you would wake up on fire."