Wintersmith
This is the third of the Tiffany Aching books.
In this one she steps into a dance she shouldn’t and the Wintersmith – the spirit of winter – falls in love with her.
So somehow Tiffany has to save the Discworld from perpetual winter while continuing her novice witch training.
This continues the high standards set in the previous Aching books, The Wee Free Men & A Hat Full of Sky.
Pratchett continues to be on beautifully bittersweet and humourous form while Tiffany grows up to fulfill her destiny as a witch of remarkable power.
I wouldn’t read it as a stand-alone (though you probably could) it really does work best as part of the sequence.
In that case I wouldn’t give a moment’s hesitation in recommending anyone to read this book