Still in season six I believe.
Each sister has her own little arc in the book as a plot point that kind of comes together in the best, worst and comical of ways.
Piper and Leo are supposed to be going out to celebrate their wedding anniversary (not stated but that would probably be their second, third or fourth?) with Paige baby-sitting Wyatt. Leo as a Whitelighter to other witches has a new charge, a twenty-something young woman named Kerria who cannot stay out of trouble with demons and warlocks.
Leo cancels so Piper is mad but since she is already dressed nicely, Phoebe asks her to be her plus one/date to a charity event fundraiser for a museum. While they are gone, Wyatt catches a cold so Paige does a spell to vanquish it so you already know this will come back to make life miserable in Halliwell Manor.
At the event, a handsome and blond young man steps up to the microphone and after a few technical difficulties introduces himself as Daniel Lemond. He is one of the organizers for the event (at the Modern Art Museum, we learn.) and Phoebe becomes smitten with him. Piper urges Phoebe to go and talk to Daniel but the moment she gets him alone; Daniel bolts out of there. Phoebe has no idea why.
Two days later, Phoebe gets daises delivered to her at work and a surprise visit from Daniel. He asks her out on a date for dinner the following night and Phoebe finds most of the conversation is Daniel wanting to know about Phoebe and share nothing about himself. He drives her home, and Phoebe invites Daniel inside, but it seems now that he can't get away from her fast enough...again.
In between Phoebe's A plot, Paige ends up catching Wyatt's cold then uses the spell on herself so that Piper and Leo can go on their make-up anniversary date. Leo ends up catching "the cold" next in the mash-up of the B and C plots.
Daniel calls Phoebe at work and asks her to come over to his apartment so he can make them dinner and explains that he thought Phoebe was moving a little too fast for him and he freaked out. This time, the date at his place is perfect and yet the only thing Phoebe finds out is that Daniel has a way with animals when he walks her to her car and two kitties demand belly rubs.
Yet when she shows up to his apartment to surprise Daniel the next afternoon, Phoebe has the door slammed in her face by a clearly agitated Daniel. He calls the next morning to apologize for being rude, but his apartment was messy, and Phoebe understands but her sisters don't. The next time they meet up for a romantic night, Daniel has plans to do chocolate dipped strawberries, but Phoebe is allergic to them.
Daniel freaks out and says the date is ruined. Speaking of dates, Paige cured Leo's cold, but he orbed out on his and Piper's anniversary plans yet again. Now, Phoebe has "the cold" but refuses to just stay home as she wants to make the plans for her date with Daniel this time. Going over, Phoebe is surprised to find Daniel talking with an elderly woman.
Her name is Olive, and she is a greeter at the farmer's market where Daniel went to buy fresh tomatoes to make sauce for a pizza. The old lady followed him home, but Daniel had been answering a call on his cell phone so didn't notice until she followed him a block away!
Daniel doesn't know why and neither does Olive, but she says Daniel is such a nice boy and then leaves. Phoebe's plans to go to a reservation at a restaurant end when Daniel refuses to leave the apartment and make her pizza instead. Being sick to the point she can't even hear clearly, Phoebe tells Daniel she is leaving and goes home.
It is then at this point when the sisters think something supernatural might be going on with Daniel and the demon angle comes into play. 80 pages into the start of chapter six. It is also around this moment that Paige thinks something might be wrong with her powers, but we all know it was the personal gain thing, right?
Sweet Talkin' Demon would have made a very interesting Charmed episode. A little more light-hearted so if that's the kind of plot you prefer instead of darker or depressing this Charmed tie-in novel is perfect for you.