As everyone says at the start of every story (so much so that you'd have thought they'd just add it to the top of the page instead of keep making people type it) I don't own these characters, well I did make Lily, but really that's just a way of getting all of "grown up" Willow's power into series one Willow's sweetness, but with a touch more backbone...
Oh, she may be a tad of a Mary Sue, but hey if you see that happening give me a nudge in the comments and I'll try and get her put down a peg :P
After the potentials were all activated, the demons of Earth really didn't stand much of a chance, some of them put up more of a fight than others but after a decade or so they were pretty much all gone except for those that were willing to "play nice" or those with secret long term plans. The SWWXC (Slayers, Watchers, Witches and Xanders Council, Xander having become an in joke name for all those who wanted to help out with the fight against darkness without fitting into the other categories, despite Xander now being one of the main watchers) or New Council was running so well that apart from the yearly apocalypse even Dawn could go an entire year or more without seeing a single vampire or being kidnapped once. In short Earth was fixed, they'd won the war... but could that be enough? All the demons that had fled to other dimensions were still there waiting for the girls to become complacent, or just wrecking things there instead. It was Dawn's idea to expand their jurisdiction to ALL of humanity, after all several of the gang had ended up in alternate dimensions whether by accident or as part of a master plan, and that was a lot of people who didn't have a slayer to protect them, while Earth, or their Earth anyway, had a surplus.
When Lily, Willow's daughter, was finally old enough to help out they'd gotten the matter down to a routine... first a survey team went to explore any new universe they made contact with, finding out if there were humans, and if there were how well they were being treated, then there was a discussion, then a more thorough exploration if they had found humans or a battle plan etc. They'd even set up an envoy of sorts in each of the "sister universes" they had helped where someone could contact them if the demons came back, and had one of the witches check in on each of them once a week.
Today they would be sending a team to survey a new universe none of them had been to yet, like every such team it was made up of two slayers, a watcher or Xander, and a witch, and Lily was finally going to get to be that witch.