Bob is the husband of Ethel Rainicorn, and the father of Lady Rainicorn. He has a short body, is horizontally-striped with rainbow colors, is almost bald, and wears glasses due to poor vision. It is unknown if male Rainicorns have shorter bodies than females, or if he's just a short Rainicorn. The fact that Ethel is long and Bob is short may be the reason that Lady is medium-lengthed. Also, he chooses to use the Universal Translator, unlike his daughter, which means he speaks Korean like his daughter and wife. Unlike Lady and his wife, his head is blue instead of pale pink.
When one looks closely at the photo of the dog who saved Bob's life, it shows that, interestingly enough, the dog is in handcuffs, regardless of his deed. Adam Muto has confirmed the dog was captured.
Bob and Ethel Rainicorn live at 47 Rainbow Street.
His hair is a pale blond; however, in the photo of the dog who saved Bob's life, his hair is the same color as his skin.
Bob is credited as "Rainicorn Dad" in the end credits for "Her Parents," as opposed to his real name. Ethel, however, is credited by her proper name.
Though speaking Korean, his mouth movements match what the translator is saying.
In the picture of Bob and the dog, Bob's hands are a light blue, but when Bob and Ethel visit, Bob's hands are green.