Bellamy Bug appears in Finn's imagination in the episode "Rainy Day Daydream." He speaks with a British accent and claims to represent Finn's secret desire to be civilized. He offers Finn a doily soaked in the tears of his daughter, who had just broken up with a gentle dandy. He is then smacked by Finn, who uses his imagination to turn the bug's arms into a robot arm and an octopus tentacle, which both proceed to pommel him. He is then carried away by a group of penguins.
Bellamy Bug is a light green bug that has the same color as Finn's pack. He also has a dark green stripe in the middle. He wears an orange fedora adorned with a blue ribbon and a pink feather, as well as brown boots and a monocle.
Good morrow, sir! My name is Bellamy Bug. Would you care for a crochet doily my daughter made? She imbued it with her tears. You see, she recently broke up with a gentle dandy.
Oh ho ho ho, I don't know, my young fellow. You tell me. Perhaps I represent your secret desire to be civilized!
- He has characteristics of both worms and insects. However, this could be because Finn imagined him.
- It is unknown if there are animals like him in Ooo.