Meaning of "Hatha Hill" by The Mountain Goats

The mention of sugar on different parts of the body could be a metaphor for the sweetness or allure that the person exudes. The signals being sent could represent subtle signs of affection or interest, and the speaker's recognition of these signals shows a mutual understanding between the two. The familiarity with the "trick" mentioned implies that the speaker has been in similar situations before and understands the unspoken language being communicated. Overall, the lyrics convey a sense of connection and shared understanding between two individuals, despite not explicitly stating the nature of their relationship.