Every Pratchett has a theme, or a parody.
Unseen Academicals is Romeo and Juliet with soccer.
Honestly, not too interesting. The main protagonists are a candle dribbler turned soccer coach and a pie-baker. Even though Rincewind makes a cameo, he doesn’t do much except for pinballing a football with the back of his head.
There is a story of personal growth, of rising above the expectations and prejudices of people. The other story is of living up to the expectations of those same people.
One of the most interesting Pratchett metaphors in this book, is the Crab Bucket.
For every crab that finds the strength to attempt to crawl its way out of the bucket, other crabs who’ll pull it back down. That’s why you can keep crabs in a bucket without a lid.
An eloquent metaphor for the lower denizens of Ankh-Morpork. Or everywhere else.