Mandy is a title character from the television series The Grim Adventures of Billy and Mandy. She has blond hair with a black head band, wears a pink dress with daisy pictured and wears black Mary Janes without socks. She is voiced by Grey DeLisle.

Personality

Mandy is Billy's closest friend, although a completely contrasting character: a blonde girl with an acerbic, never-smiling attitude (yet has a devious smile on the inside), evil personality (she believes in the abuse and exploitation of the stupid), and often surprising intellect and knowledge of the supernatural. She is rude to practically everybody, even her parents. Originally just somewhat of a downer, she has since become completely sadistic and dark; her role with Billy has also changed from a good friend to ruling over Billy, constantly bossing and abusing him. She is a fearless fighter who will stand up to schoolyard bullies (Billy and the Bully) and monsters from the underworld (Irwin Gets a Clue) without flinching (a fawning Irwin has described her as a "tiny Valkyrie").

Her relationship with Billy can be characterized as brother-sisterly: They argue, fight and insult each other, but they stick together. Their relationship is platonic, but it is suggested that there is some kind of romantic attachment between them, as they spend a lot of time together although they are completely contrasting characters. Mandy's relationship with Grim ranges from domineering to grudgingly respectful, although she frequently appoints him to perform humiliating chores and never lets him forget that she "owns" him. Grim and Mandy also share an almost mutual understanding perhaps because they have equally dark sides (even though Mandy's could be debated as darker) and often seem to enjoy each others company more when Billy's not around.

Mandy personality is also quite a mystery. Billy inherited his stupidity from his father but where Mandy got her dark evil-like character is uncertain since her parents appear rather normal. It couldn't be environmental since Billy said that Mandy has been what she is since birth featured in My Fair Mandy. Due to her personality (most likely) wolves tried raise her as their own, as her father Phil tells the court in Keeper of The Reaper.

Since Mandy spends most of her time at Billy's place we don't get to see much about her family and their life together. But from what we've seen so far Mandy has an iron grip on her parents and more or less controls them with the power of her "evil". It's also unsure whether Phil or Claire loves her, as in Keeper of The Reaper Phil says that it's not that they don't love Mandy, but they're scared of her. But then in Scary Poppins when Claire is supposed to tell Phil she loves him, she spots Mandy outside the house (after being kicked out of Billy's) and screams "And I love... Mandy!!" upon Phil replies, shocked, "You love Mandy!?" "No...!". They most likely keep up appearances as loving parents when they're not alone together.

Mandy's smile

Mandy almost never smiles, aside from the occasional evil smirk. The only exceptions thus far have been in:

• Meet the Reaper - at the end of episode just after Grim says 'I Loathe You'.
• Opposite Day - shortly after Mandy calls Grim to the lawn, Mandy gives a quick, sarcastic smile.
• Look Alive - Mandy smiles while giving Grim a makeover. She also gives two other sarcastic brief smiles in the episode.
• Dumb Wish - after realizing what she had done after wishing that all people of the world would disappear.
• Get Out of My Head - when Billy jumps into her head and possesses her, causing her to behave with Billy's blissful, cheerful stupidity.
• Dream a Little Dream - A split second before Mandy closes the fridge door, thus ending the episode, an evil smile is visible.
• Crushed - During a fantasy sequence in which shows her falling in love with Billy's friend Piff.
• Test of Time - In the end of the episode, when the entire world is Billified.
• My Peeps - Smiled in a Billy's fantasy, in which he was seeing everything as a colorful toddler show
• My Fair Mandy - when she is performing as Dorothy Gale (complete with braided pigtails and blue gingham dress), singing Somewhere Over the Rainbow for the talent portion of the school's "Little Miss Scurvy" pageant. This smile is so anomalous that it destroys the universe, transporting her, Billy and Grim to a ' Powerpuff Girls- like universe, in which the three of them are recast as Blossom, Bubbles and Buttercup (in the end credits coda, we also see Irwin recast as Mojo Jojo, struggling to breathe in the villain's tightly-cinched costume). Like in the most episodes, this reality-shifting change didn't effect the continuity. Also, according to Principal Goodvibes, the smile is apparently so beautiful that (despite the collapse of the Universe) his eyes fly out of his eye sockets with tiny little wings.
• Billy and Mandy Save Christmas - After singing a Christmas song to get Santa Claus to have Christmas cheer again, Baron Von Ghoulish and Grim take two candy canes and pull her mouth into a wide grin.
• Billy and Mandy Begins - When Mandy first appears in Billy's story, a real-life picture of Grey DeLisle's smiling lips replace her animated mouth. Mandy in the supposed real-world (outside of Billy's story) notes that she looks ridiculous.

Trivia

• According to the subtitles in the episode Dream Mutt, Mandy is "Billy's friend, napkin collector."
• Mandy's personality is similar to Raven from the Teen Titans animated series, and Cartoon Network has joked around with this by putting the two together in Cartoon Network Shorts. In one short, Raven and Mandy sit on a subway, and as Mandy exits the train, she says, "Nice chatting with you," to which Raven responds, "Whatever". On Mandy's own fictional TV Show called, "The Darkside with Mandy", Raven sent a letter saying the show wouldn't last another week, in which Mandy replied with "Get a life, parakeet". Mandy also once said to Raven, in a commercial short, that " she should wither away because no one is going to carry her weight around for her" and to "deal with her problems in a professional manner and then shut up."
• In the episode Attack of the Clowns, Billy notes that she has an irrational fear of professional figure skaters, although her fear was never manifested. The excuse she gave - "I just don't trust the way they spin is all" - might hint at her awakening interest in the political sphere.
• Mandy appeared in an episode of Foster's Home for Imaginary Friends, The Big Picture, returning an imaginary friend because it was "too happy".
• Meet the Reaper is the only episode in which Mandy wears socks.
• Mandy's hair looks like devil horns.