Theresa Fowler is the love interest of Randy Cunningham from Randy Cunningham: 9th Grade Ninja. She is friendly, kind and compassionate. She is also a member of the Norrisville High Twirl Team at Norrisville High. Most of her appearances have shown that she has feelings for him. She is impressed with his bravery and nicknames him hardcore making him as her protector. She also looks to him for her safety and leadership. She also holds his hand during frightening moments and occasionally gives him a reassuring or caring smile. She worries about him when he disappears to become the Ninja in a latter episode. She seems to believe that he is a hero and he is her hero and she often reacts to him positively. In "Shloomp! There It Is", Randy flirts with Howard's older sister, Heidi and she transformed into a monster. After she reconciled with Theresa and apologizes to her and she was turned back to normal. In "The Ninja Identity", she was saved by him as the ninja as she shows a lot of gratitude as she thanks and hugs him, showing that she has romantic feelings for Randy and Randy shows that he loves her. In "Sorcerer in Love 2: The Sorceress's Revenge", she prasies the Ninja for saving her and her classmates. She serves as the primary love interest for Randy.