Gil is the leader of the Bubble Guppies along with Molly. He is good friends with Goby, Nonny, and his best friend Molly who he has feelings for. Gil is sometimes the important boy and mostly sings in the dance songs, in the pop songs he is singing background, in I Need To Rock! Gil sang the pop song instead of Molly. Gil is an energetic guppy boy which is why people may hang with him. He is also Goby's best friend. He is a bit hyper, if he sees a ball, he may throw it; if he finds an electric guitar, he would play it; and if there is a pig costume around, he will be oinking. Gil's upbeat energy and insatiable curiosity is infectious, so he is encouraging others to join in his adventures. Goby is his best friend after all. he will always deliver some slapstick humor. He is often the subject of a continuing joke that repeats during the episodes. Alongside of Molly, he sings a few of the pop songs. His favorite food is Pizza and Apple juice. He loves playing with his best friend Goby, and they are kind complements to each other. Whatever problem Goby has, Gil can help.
Gil has bright-sapphire blue spiked hair, blue eyes, and a marine-green spotted camoflauged-patterned tail. He is a fair cacasion with peach skin, and if he has his head turned left or right there may be cowlick-pieces of hair that stick up on the back.
Gil was thought to be quite short in height on the early depiction of Bubble Guppies. His body was very skinny but wide, his hair was flat like Goby's but it was somewhat spiky. Gil's fingers were long and round, and his tail was very thin.