You REALLY need to implement a failsafe for possession duration. I've now been stuck in non-player-controllable possession situations for ~15 minutes or more three times because there's no maximum limit on how far apart each struggle chance is, and no guarantee that it'll work when it does. At some point, losing all agency becomes rather unfun.
If you mean how Glace takes control away from you and you spend several minutes watching lines about how Celica is helpless, then this should be fixed in the next stage of the game's development: Deimus gradually makes the game less linear, but it is difficult to do right away, since at this stage of development players need to have all the new scenes available to them.