Just WHO OR WHAT are the Tokonatsu Sisters anyway?
Was there ever an explanation as to what happens to the Alters after they stop being used? Or more importantly, the matter that gets rebuilt into the Alters? It seems like they just disintegrate into nothing without the matter used to build them coming back.
A likely explanation is that it converts back to energy in order to preserve the conservation of mass and energy. The alter power converts mass to energy back to mass, nothing says it'll turn back to energy. However, as we never see anything physical appear to replace the mass the alters use, this'd be this troper's best guess. Kazuma's initial defeat during Ep 10 kinda sorta demonstrates this.
Why was Ayase given a device that actually monitored her brother's heart beat, instead of a device that merely acted like that and just telling her that it monitored her brother?