Owned by the doting Lord Emsworth, the Empress is an enormous black Berkshire sow, who wins many prizes in the "Fat Pigs" class at the local Shropshire Agricultural Show, and is the subject of many plots and schemes, generally involving her kidnap for various purposes.
"Pig-hoo-o-o-o-ey", wherein we first meet the noble beast, tells of how she misses her first keeper, Wellbeloved, when he is sent to jail for a spell; her pining is worrisome to her master, with the big show approaching, until she is pepped up by James Belford's hog-calling techniques, returning to her trough with enough gusto to take her first Silver Medal.
Soon afterwards, to Emsworth's disgust, Wellbeloved defects to Sir Gregory Parsloe-Parsloe, whose own animal the Pride of Matchingham is the Empress' biggest rival.
In the novels Summer Lightning and Heavy Weather, while she is under the care of Pirbright, she becomes the subject of various schemes: first stolen by Ronnie Fish (who has upset his uncle by bouncing a tennis ball on her back and hopes to get back into his good books by "finding" her again), she is stashed in a gamekeeper's cottage in the woods, and fed by the admirable Beach, but later moved by Hugo Carmody to a caravan owned by Rupert Baxter.
When he finally gets past Monica Simmons' able guard, he finds the Empress suffering from a hangover, Wilfred Allsop having dropped a flask of whisky into her trough the day before; she bites his finger, and Emsworth's fears that she may be in danger of infection prove priceless to his own happiness[clarification needed].