Erastus Bitterbug

Erastus Bitterbug, usually referred to as just Bitterbug, is one of the main characters of Walter Melon. He is the long-suffering assistant and partner of the eponymous Walter Melon, and accompanies him on double-replacement missions. Notably, he is not present in some episodes (due to only one replacement being needed on some assignments).

Physical Appearance
Bitterbug is a thin, dark-haired male who has a fair skin colour with a big, round nose and a moustache consisting of six thin hairs. His clothing usually consists of his trademark circular glasses, a shirt and jacket (whose colors tend to vary depending on the episode), black pants, and sometimes a white cap.

Personality
Bitterbug's character contrasts heavily with his associate's; typically, Bitterbug is far more nervous and meek compared to Walter's confidence and bravado, and is prone to sarcasm, especially in undesireable scenarios. Often, he'll suggest to Walter that they should give up, but this motion always goes ignored. He routinely bears the brunt of any mission, getting crushed, thrown, or smashed into objects and/or the floor, which likely explains his worrywart nature and reluctance to engage in adventures.

Trivia

 * Bitterbug's first name is never mentioned on the show. In fact, the only place it is mentioned is on the character introduction page of Walter Melon - Magnesia's Treasure, the only comic of Achille Talon ever officially translated in English.
 * Bitterbug's original French name is Hilarion Lefuneste, a pun on le funeste (French for "the fatal/disastrous").
 * In "Big Red Riding Hood and the Pizzas", Bitterbug is revealed to have replaced Sneezy, one of the seven dwarfs, before meeting with Walter.