Looks very interesting.
I found a hallway with pictures on the side, you can look at them with E but to stop looking you need to click the mouse or press ESC. Would love if you can exit those with right mouse click, E or another button on the keyboard that is not ESC. That goes for instances too, if I click into something I would love to click out of it too, keying in - keying out. To enter the upgrade menu you need to click the card of a character and then click it again, found out by messing around.
I did not loose to the toilet keeper, so I don't have her losing scene in the gallery. Losing to the imps with a full time takes ages. Maybe unlock loosing scenes in an alternative way?
You need knife and coin to upgrade the companions. You need horn and coin to upgrade main PC. An alternative would be different materials for offense, defense and ability. If that would be better or not I don't know. Kind of depends on how many characters there are in the end. And if main holds up, cause farming one ressource more often than another could be rather tiresome.