Although Coach Gills looks rather sweet, she's no pushover. She never hesitates to give Adam a hard time if he doesn't perform as well as his fellow students.
Coach Gills is very dependent on Horace, not being able to move anywhere without him. Horace serves her hand and foot and she barks out orders in return. In "The Magic Fish", she said that she had no friends, much to the disappointment of Horace. Coach Gills ignored him, saying their relationship is strictly professional.
Coach Gills is the one who paired up Adam with Jake. She has always been the hardest on Adam, because he is the weakest. In "Le Switcheroo", she and Adam trade roles for a day. After experiencing some trouble, they at last reconciled.
- Her deep, manly voice often gets her mistaken for a male, by other characters and outside viewers alike. The only overarching things that prove her feminine gender would be her eyelashes and her tiny blue bow on her top fin.
- She has mentioned several times in the series that she has no friends.
- She once had a crush on Mr. Cheetah, an athletic individual who plans to succeed her and Principal Pixiefrog in their careers.
- Although she is a fish, she apparently cannot swim.