Many people are horrified by bugs; some are fascinated by them. They may frighten or annoy us, but in general, members of the class Insecta stir reactions considerably out of proportion with their body size. These reactions — both in character and in reader — are easy fodder for the writer.
PROMPT
You could go absurd and imagine a vast cockroach on the scale of the one that Gregor Mendel becomes in “The Metamorphosis.” You could use bugs as an overarching theme as A.S. Byatt does in her masterful novella, “Morpho Eugenia.” Or, just have your character get stung by a bee or bitten by a swarm of mosquitos. One way or another, use an encounter with an insect to explore a character’s psyche.