Mabel Pines is a bouncy, energetic, optimistic, hyperactive, enthusiastic, and free-spirited 12-year-old girl spending the summer with her Great Uncle Stan in Gravity Falls, Oregon, where she and her brother frequently encounter the supernatural, and is soon joined by other children with similar experiences.
Being the the happy-go-lucky one of the group, she takes a much less serious approach to life than her brother and some of her friends as she navigates her way around odd, new surroundings.
Mabel is a short 12-year old girl, exactly one millimeter taller than her twin brother. She has round blushing cheeks, long brown hair that reaches her hips, her eyes are the same brown as Dipper's, and she has silver-colored braces. Mabel's apparel varies for each appearance, more so than any other character's, with at least one new outfit usually consisting of a sweater, undershirt, skirt, headband, black shoes, white socks, and occasionally earrings, though she does deviate from this look occasionally.
Mabel Pines is an optimistic, fun, and energetic girl full of spirit. She is an optimist who skips through life with a braces-filled smile and an assortment of extremely colorful knit sweaters. It is her outgoing personality and fearless curiosity that comes in handy when her friends needs help solving a mystery, even if she isn't always aware of her silliness. Mabel is aware of her charm, and cherishes her cuteness and beauty.
She is a preteen dreamer with a world filled with preteen novels (mostly about vampires), and her fixation on finding her one true love occasionally lands her in sticky situations which ultimately require her brother's help. Still, despite all the weirdness in Gravity Falls, Mabel is always a "glass-half-full" kind of girl. She is rarely angry or upset, and generally keeps a positive outlook. She is somewhat naive at times.
Mabel is aware of her charm, and cherishes her cuteness and beauty. She has also shown to be self-righteous in her decisions, which can be far from justified, or they may accidentally backfire in some way. As she got older, Mabel will take certain situations with utmost seriousness when it is required though she will throw in a quirky one-liner here and there simply to lighten the mood. Her experiences with the supernatural and the extra-terrestrial has "widened" her perception of the world around her, thereby, becoming more adept to situations involving the paranormal or otherwise. Despite being what Dipper remarks as "battle-hardened" from her adventures, she never loses her cheerful and optimistic disposition.
Role in the Story
The story begins is Mabel making a sweater with hundreds of buttons sewn into it. When Dipper found her making the sweater, Dipper criticized her for making it. When Dr. Loboto arrived at the Mystery Shack, he was looking for brains and Mabel supplied him with a brain in a jar. Not satisfied with it, Loboto rudely tossed the jar onto the ground and, after Loboto acted shamefully, Dipper told him to leave, an act that made Mabel clap for her brother. Unfortunately, Loboto had other plans and tried using a large drill on the twins.
After avoiding Dr. Loboto for awhile, Mabel threw the journal out of a window and tried using her grappling hook to make an escape for her and her brother, but the mad dentist prevented this. This prompted the twins to physically attack Dr. Loboto to make a break for the golf cart outside of the Mystery Shack. Their plan successful, the two departed from the Mystery Shack while Dr. Loboto got his car ready.
In the woods, Dipper and Mabel saw Coraline's phone fly by as they were driving. They then heard the sound of an engine starting, prompting them to flee immediately in fear that Dr Loboto was close. After awhile, the twins almost ran over Coraline and her friends, crashing the golf cart in the process. After a brief conversation with Coraline, the twins were confronted by Dr. Loboto with the intention of destroying them. It wasn't until the untimely arrival of Rasputin Aquato and Lili Zanotto that the children, including Mabel, were able to fight another day.
Back at the Mystery Shack, unlike the other Mystery Kids, Mabel was goofing off for the most part, dressing up at Dr. Loboto to make fun of him, although her costume did cause Coraline to have a panic attack because Mabel used buttons to represent Loboto's eyes. After Norman was able to get everyone to work together, Mabel decided to start an 80's montage while everyone, including herself, were at work preparing for their upcoming fight with Loboto. During said montage, she and Dipper were looking through various weapons to see which ones they could use. After the montage was over, the team ventured into town, with Mabel riding Waddles as her steed.
At the junkyard, the gang fired a net at something they thought was Dr. Loboto. When Mabel looked to see who or what it was, she discovered it was just a beaver and hugged it. When Dr. Loboto actually showed up, Mabel was tasked with providing a diversion. Eventually, the children defeated Dr. Loboto. After the battle and Dr. Loboto's arrest. the children celebrated. An exhausted Mabel called the group "The Mystery Twins", but Dipper pointed out that there were more than just two people. This prompted mabel to come up with an alternative name for the group, though it was Neil's idea of calling the gang "The Mystery Kids" that ultimately stuck. When it came time to pick a team leader, everyone went with Coraline, with Mabel complimenting how awesome Coraline was. When Perry Babcock arrived to the Mystery Shack to pick up Norman and his friends, Mabel waved at them and left the door to the Mystery Shack open, with Coraline and the others eventually sneaking back in. A while later, after Lili read Coraline's mind and embarrassed her, Dipper and Mabel had their minds read as well and they are also embarrassed.