Marriage
The main theme that is prevalent in most of the stories in the collection is the theme of marriage, more precisely unhappy marriage. Often, there is a husband that doesn't take his wife seriously, and a wife whose contempt for her husband grows as the days pass. The stories that portray most prominently that type of relationship are "William and Mary" and "They Way Up to Heaven". In the first mentioned story, we have a dying husband who even after his death tries to control his wife by exhorting his views upon her, and a wife whose contempt for her husband and years she spent serving him are at the highest point, and at the end where there is only a brain and an eye left of him, he seems the most perfect to her. "The Way Up to Heaven" shows an old couple, a nervous wife and a husband who enjoys making her suffer and increase her anxiety. The wife finally realizes that her husband has been intentionally making her late for every trip, to increase her anxiety, and using his power over her to make her silent. It is clear that the view of marriage is not a positive one in the stories; the author portrays it as a prison its participants willingly get themselves into.
Appearances are deceitful
In "The Landlady" the old lady seems perfectly harmless, but it's revealed at the end that she is behind disappearance of several young men through the years. The "Parson's Pleasure" portrays the main character who uses a disguise of a parson to profit from deceiving and selling the antique furniture he finds in houses of people living in countryside. In the "Mrs Bixby and the Colonel's Coat" the wife underestimates the value of her husband who is revealed to be cheating on her the same way she is. The stories are also structured to have a hopeful beginning for the protagonists, but they end with abrupt, and most often gruesome twist.
Horror
Of central interest here is the type of body horror that brings disturbance and unease. From the first story, "The Landlady", this type of horror is shown prominently, since it's understated that the old woman kills her victims and then stuffs their bodies to make realistic replicas. Another, more explicit example of body grotesque is "William and Mary" where William's brain and his eyes are preserved by a fanatic doctor making it so that William continues to live in that form. In the "Royal Jelly" the main character is a bee-keeping obsessed individual who discovers health benefits of royal jelly, consumes it and makes his baby consume it. This results in them starting to look like bees. "Pig" is probably the most gruesome and horror-themed story out of them all, which uses the similarity between a human and a pig in a grotesque manner.
