Plesiomon is a Dragon Digimon. She lives in an underwater grotto hidden inside ruins next to a ship graveyard in DigiQuartz. When Mizuki makes a hole in the barrier [[Dragomon ()|Dragomon]] is trying to destroy, Plesiomon tells Mizuki not to break it and to leave immediately. After Mizuki, [[Submarimon ()|Submarimon]], Tagiru Akashi, [[Gumdramon ()|Gumdramon]], Taiki Kudou, [[XrosUpShoutmon (Kamemon) ()|XrosUpShoutmon (Kamemon)]], Ewan Amano, and Airu Suzaki arrive at her grotto, Plesiomon asks why they have broke the barrier, and requests them to leave. She is then hit by Submarimon's "Oxygen Homing" when a hypnotized Mizuki decides to hunt her. After Dragomon arrives at the grotto, she starts fighting him, but is thrown in the wall. When Mizuki tries to get the [[Digi-Egg ()|Digi-Egg]] P