You can
NOT do it in this version of the game, because although it has some of those images/renders with Sasha already packed in, it has
NO dialogue or code to trigger more events for those characters. In my previous comment I simply meant to reflect that not every items in the game has any use in this version. Maybe in the next version of the game.
In any scene in the game, you can go backwards by pressing the
PageUp key
go back, open the inventory and use the red potion bottle to recharge Sophie's green bar, if you have bottles to do so.
And if not use a cheat.
Level 30 or 31 I think, but I used the cheat (LVSo =) with some boss.
In many scenes of the game you have 4 paths, choose the one you want, and if it wasn't the right one press the
PgUp key to go back to the previous screen, and choose another. Or use
Save/Load, to save the game before doing something, and then reload it to choose another option