Legal Drug - Crossover With Other CLAMP Works

Crossover With Other CLAMP Works

In the second volume of Legal Drug, Kakei purchases clothes from "Piffle Princess" for Kazahaya to give to a girl from Ohto High in exchange for her uniform. In Angelic Layer, this was a store selling Angelic Layer merchandise and where people could practice fighting with their Angels. In Suki, Piffle Princess appears as Caffe Piffle Princess, a café frequented by the main characters. Piffle Princess also appears in other CLAMP works, including: Chobits, xxxHolic, Tsubasa: Reservoir Chronicle, and Cardcaptor Sakura.

In the world in which Legal Drug occurs, Piffle Princess appears to be a popular clothing store. A dress from Piffle Princess is given to a student at Ohto High (私立桜都女子高等学校, Shiritsu Ōto Joshi Kōtō Gakkō?) also known as "Barf High" (ゲロ高, Gerokō?) (The Japanese word for vomit (謳吐) is also spelled Ohto), Hinata Asahi from Suki; Hinata, her teacher Shiro Asou, and Ohto High all appear in Suki as well.

The Atashi character from Chobits also appears, such as on a clock in the Green Drugstore.

Rikuo and Kazahaya have both appeared in xxxHolic; Watanuki is sent out to purchase a hangover remedy and enters the drugstore where the two work. He sees ghostly images around them (Tsukiko and Kei) and observes that there is some strong bond between the two. Furthermore, the High Moon Urn Yūko Ichihara has obtained in volume 5 from the "anything store" is actually the same vase retrieved by Kazahaya and Rikuo in volume 2 of Legal Drug. It can be also noted that in volume 2, Kazahaya walks through the space between a telephone pole and a wall, as does Watanuki in xxxHolic. Watanuki, after inheriting the shop from Yuko, appears as Kakei's customer in DRUG & DROP.

The Green Drugstore and its staff have also made small appearances in Kobato. The Green Drugstore, Kakei, Rikuo and Kazahaya are identifiable in the background of Drop 5 and two characters who look like Rikuo and Kazahaya walk past Kobato in Exam 9.

Kohaku from Wish (manga) has appeared recently in this series.