|“||What the juice, Howard?! Kind of doing a live gossip report here.||”|
Heidi Weinerman is Howard's older sister and the host of Norrisville High’s Heidi@School, where she updates everyone on what's happening at school.
Heidi is tall and slender, having orange hair, deep blue eyes, and a beauty mark on her left cheek. She wears a cream-colored shirt, the sleeves ending at her elbows, with red on the collar, sleeves, and bottom. She also wears a red bracelet on her right arm, a dark brown skirt, long white socks, and red dress shoes.
Heidi is on the cutting edge of everything and anything. She apparently likes attention and publicity because she spends most of her time on her show, Gossip Report. She's very determined. In "Grave Puncher: The Movie!" she did not let Howard and Randy's escape to the theater from practicing for her drivers test. She has won the Battle of the Bands for the last six years, and only failed to win the most recent one because Howard damaged her guitar, making her angry at him. However, she does show genuine appreciation and gratitude to those who do something kind for her, like in the same episode, she was grateful to whoever returned her guitar. She also thanked Randy when he told the truth about sneaking out to watch a movie to her parents and took the blame, although still not remembering his name.
She does not get along well with her younger brother, Howard, annoyed when he came to ask her for lunch money and threatened to embarrass him if he and Randy would ruin the Norrisville High Talent Show. At first she believed that Howard knew the Ninja's identity, but got angry at him when he supposedly didn't, saying she knew he hadn't. She is rude and impolite to her brother and likes to challenge and insult him. Both of them enjoy popularity but she is far better at getting and keeping it. She doesn't seem to care about Randy when she's around him and Howard, showing how little she cares about her brother and anything involving him.
Although he says he's known Heidi his whole life, she seems to barely know him and always forgets his name, calling him "Andy", "Sandy", "Mandy", "Tandy" or "Rudy". She doesn't seem to care about him in the least whether he is with or without Howard. She is willing to make use of him, though if it's to her benefit. She uses him as a back up judge when Bash betrays her. Randy explains that his and Howard's escape isn't Heidi's fault, impressing Heidi so much that she thanks him--although, much to Randy's chargin, she still forgets his name. She also gives him credit, albeit messing his name up again, for apologizing to Theresa and giving her flowers in "Shloomp! There It Is!". However, she is disturbed when Randy--who at the time was NomiRandy--flirts with her.
When Randy is the Ninja, Heidi is very fond of him. She sings a song about him for the Battle of the Bands, and she usually has nothing bad to say about him, unlike his other identity.
While Heidi doesn't interact much with Theresa before "Shloomp! There It Is!", she is affected when NomiRandy ignores Theresa to flirt with her. When Theresa is stanked, Heidi becomes her target, much to Heidi's horror. She even tells Theresa that she barely knows "Andy," but it only angers Theresa because she said Randy's name wrong. Captured by Thersa, Heidi pleads to her to not hurt her because they're total biffers, although once the Ninja shows up, Heidi tells him to waste her. Since then, Heidi and Theresa can be seen chatting in the backgrounds of "Welcome Back Catfish" and "M-M-M-my Bologna", suggesting that they might be friends.