without pause, back and cancel buttons in game for gameplay and battles it will cause frustrations to every player who plays this game will eventually got stuck with no back or cancel option to choose a different option. 1. Ether add those or don't put Android for this game at all. 2. No pause, back and cancel buttons in game equals android unworthy think about it.
I apologise for the offence but still, when i play this game if I got stuck it really frustrates me like really bad and I have start over because of no back button to exit out of something like pause menu and battle choices to save progress before jumping on what started. So like I said I'm sorry but still.
Technically it has a pause option for until you make the choice the event won't proceed further. And since this fight is a part of a linear scenario quest there's no sense in exiting it - you'll have to play it anyway. Also we have the autosave before the fight so if you just exit the game you can start straight from the fight.
Adding saves in the middle of the fight can break the linear script when loading, plus the option of saving anytime or canceling a choice may spoil the experience - people will just check each option and then load back, with no real value of the choice made. It may be harder to complete yet once you win you'll feel the victory.