NB plot spoiler below
I'm not one for reading books about football - but as with any TP book, the football is slightly skewed, and the humour and observations on life generally are what makes these books such a joy to behold.
Nutt is the slightly unusual, mysterious character we meet in Unseen Academicals - and it turns out he is an orc, but one that has been raised not knowing what he is and thus not knowing he has the potential to be a dangerous and violent character. The book has as one of its main themes the issue that race (or breed) must not be held against one, and difference should be celebrated.
The other delight of the book is Glenda Sugarbeam - a cook in Unseen University's night kitchen. She is the sensible one, the homely character and the one with the undeniable need to fall in love with Nutt.
A barnstorming football match between two universities - using the very new rules that have just been drafted makes a fitting and funny climax to another wonderful Discworld novel.