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An original character by Rakurakutei Ramen. Originally the vengeful spirit of a brutally raped and murdered girl, she was defeated by Kamishiro Seren and imprisoned in a "Jack o' Ran-tan" to get over her grudge. Eventually, she returned to her former form of a young girl with long purple hair, two "ears" of which are held up by white bows. Due to half of her body never being found after the murder, her lower body is ethereal, and can transform into a Jack-o'-Lantern to dispense chocolates, candies, and other treats.
Ran is often seen with Ujikintoki Tamaryu and Kagurazaki Shizuki. She's very quiet and withdrawn compared to the others, often replying shyly or fiddling to appear busy if not clasping her hands to her chest. This, however, doesn't tend to prevent her getting drawn into the other character's goofy antics.
Until the aftermath of Ghostrick Live, she was the only character with a consistently different speech bubble style, with semi-transparent bubbles and a rounded gothic font.
In Ghostrick Live, she is revealed to be an artificial ghost, a duplicate of a certain Etranger Shutulia that gained self-awareness and an individual personality thanks to Seren, her friends and the rest of the cast. She would eventually become whole and gain life, becoming a living ghost in the process thanks to having merged with other Etranger copies. The merging process also produced a duplicate of Ran, essentially an identical twin with a copy of her memories but with a rapidly diverging personality. She would be dubbed Ren.