On the surface, this is a breakup poem, but it refuses to make ordinary sense. The speaker describes an ex-partner through a string of absurd details: profiting from the Napoleonic wars, a moon the size of two blue eagles, a dog that whistles into the void. None of it adds up, and that seems to be the point. The ex comes across as someone grandly self-important and impossible to pin down, a person who droned on about Neptune and couldn't even bake a decent cheesecake.
The speaker's feelings come through in small, wry jabs. The "long whiskers" patting their back and the line about ginger tea suggest condescension and a mild, tired irritation. In the second stanza, the poem turns to "you," someone the speaker has chosen instead, with a "house of books." The final image, an avocado's frustration, is pure nonsense, but it lands as affection. The mood is comic and playful, with a real note of relief underneath.