The limerick used in the story can be seen as a text about two types of domination:
- domination of a man be a woman (assuming the tiger is male) and
- domination of nature by humans.
The theme of domination can also be found in the short story, in which it gets reversed. But this reversal relies on another reversal. The beginning of the story mentions Margaret of Antioch, who gets eaten by a laidly worm (a kind of wingless dragon). Because she is so virtuous, the wooden cross she wears around her neck turns back into a living tree, the tree's branches burst open the dragon's body and Margaret emerges alive. The story also mentions hamadryads, a type of female beings from Greek mythology that live in trees.
In the short story, Gilla swallows a cherry (including its stone) from a half-dead cherry tree that scares her because it seems to be talking to her. It's as if a hamadryad was living in that tree. After swallowing the cherry's stone, Gilla gets the impression that she has thoughts that can't be hers (because of the unfamiliar vocabulary), almost as if the cherry tree or its hamadryad were talking to her or inside her. The "reversal" here is the following: whereas Margaret of Antioch was wearing something from a tree on her body, Gilla has something from a tree inside her body.
Gilla goes to a party where she joins the other teenagers there in playing Postman. Roger, the boy who had calumniated her, gets someone to fetch Gilla so he can harass her. She tries to fight him off, then something changes:
The back of Gilla's neck tingled. The sensation unfurled down her spine. She gathered power from the core of her, from that muscled, padded belly, and elbowed Roger high in the stomach. "No!" she roared, a fiery breath. (...) Gilla fell onto her hands and knees, solidly centred on all fours. Her toes, her fingers flexed. She wasn't surprised to feel her limbs flesh themselves into four knotted appendages, backwards-crooked and strong as wood. She'd sprouted claws, too. She tapped them impatiently.
Roger gets scared, and when he and Gilla emerge from the closet, Gilla looks perfectly normal to everyone else except Roger, who says that, "She's some kind of dragon, or something!" (It is perhaps no coincidence that her name sounds similar to that of the Gila monster.) This is another reversal: Roger though he could get his way with her but ends up on the loosing end. When this ending is compared with the limerick, the "rider" is not a "lady" but a (very ungentleman-like) boy. And whereas his "mount" seemed harmless, she turns out to be a dragon. (The eating of the rider has the following counterpart in the story: "Gilla considered, licking her lips. Roger smelled like meat.")
At the end of the story, there is no tiger with a lady inside, but a lady with a dragon inside, at least figuratively: whereas Gilla had been uncertain about her physical appearance, she now appears confident. She asks another boy, Foster, to deliver her a "real Postman message". "Gilla led the way, grinning." This last sentence mirrors the limerick's "smile on the face of the tiger".