MSJ-105CC Chuchu's Demi Trainer (デミトレーナー チュチュ専用機 Demitorēnā Chuchu Sen'yō-ki?) is a mobile suit introduced in Mobile Suit Gundam the Witch from Mercury and is piloted by Chuatury Panlunch.

The base MSJ-105 Demi Trainer is an older model in Burion's Demi Trainer line. The MSJ-105CC is Chuatury Panlunch's customized personal unit and the result of "Project Chuchu". As students in Asticassia School of Technology's Earth House are typically unable to afford the latest, most advanced Demi Trainer models, it is common for them to purchase obsolete Demi Trainers and modify them extensively to try to reach parity with the newer models. In Chuchu's case, her unit was customized for hit-and-run tactics. It is armed with a long-distance beam rifle to strike targets from afar, and its legs feature acceleration and deceleration enhancements for rapid, precise maneuvers. The alterations to the legs make the unit difficult to control for pilots who lack high-g training, however. Although Chuchu disliked the idea of retreating and repositioning in between attacks, she eventually came to accept the MSJ-105CC's design.