Fred's dominant trait is his Trichotemnomania; an obsession with cutting/shaving people's hair to the point of complete baldness. He appears to be able to control his compulsions to a certain degree, but can't help himself when the opportunity is too great. Despite this, Fred is generally a very polite and intelligent man. He never raises his voice and is usually seen smiling. He speaks in a well mannered and eerie tone with an English accent. He is quite fond of his Aunt Muriel, keeping a framed photo of her in his briefcase and refers to her as his "dear Aunt". He appears to like Eustace as well, even if he later likes him because he shaves Courage. Eustace locks Fred in the bathroom with Courage, who becomes his shaving victim, and it appeared that Fred did not worry for Courage's feelings or well being. He tossed Courage around, stuffed his mouth with pancakes and generally was entertained by Courage's escape attempts. Fred reminisces in rhyme, speaking three rhymed sentences and ending the fourth one with "naughty

Muriel is a devoted housewife with a truly gentle, sweet, and kind demeanor. She also enjoys cooking, knitting, and quilting, though she can be ambitious where her crafts are concerned (in The Quilt Club, her desire to join Elisa and Eliza Stitch's quilt club became an obsession). She cares for Courage Deeply

Eustace⁥ is a very cynical and jaded old White man who is usually irritated and frustrated by the world around him. He is also money-obsessed and has an unquenchable thirst for monetary gain. In almost every episode, he is seen sitting in his favorite red chair while reading a copy of the Nowhere News and possibly watching his television, which he deems precious to him. He has an adamant disliking for Courage and frequently calls him "stupid dog", taking great pleasure in tormenting him whenever possible, which largely stems out of jealousy that Muriel constantly pampers and dotes on Courage. It is very common for Eustace⁥ to scare or mess with Courage, whether it's to make Courage leave Eustace alone, or just for the fun of it. In some episodes, it is also possible that Eustace⁥ himself also has a jealousy of Courage's superior intellect and talents compared to his.

Courage, as the show's title suggests, is an extremely cowardly and anxious dog that is easily frightened by almost anything. Despite this, when his owners or friends are in the face of danger, he will stop at nothing to save them, which easily makes him the bravest and most morally-aligned character throughout the series, living up to his name. Though he is willing to risk his own life to protect Muriel at all costs, his irrationality sometimes causes others to doubt his intuition. Courage has been presented as an almost entirely selfless character, working to benefit others with usually little to no regard for his own well-being, risking his own life dozens of times simply to assure his owner's safety.