The main protagonist of FLCL: Progressive. Hidomi is antisocial and tends to ignore reality and the events around her. She is nihilistic and gloomy, often having morbid dreams of a desolate world where she is hurt in some way. She softens around Ko Ide and she carries a mutual crush on him. Haruko and Hinae describe her as a “tsundere” character. She apparently has a strong will, since she is not affected by Haruko's mind control attempt. At the end of the story, she does soften, as shown when she makes up with her mother and begins a relationship with Ide.

Being the silent type character she is, Hidomi doesn't have as many lines as a normal protagonist would. She has a quiet yet decisive voice.