From the comments I see that many people (myself included) hate that 2 kobans button. I've lost some kobans only for clicks error.
Really you have to farm money from the harem pretty often and paying 2 kobans each time is... well almost noone wants to throw away money for such a trivial thing.


My suggestion is: change the price for that action from 2 kobans to X energy. Where X can be a fixed number or maybe depends on how many girls are farm-ready (1-2-3 energy for each girl?).
Pros:
- right now energy is only needed to advance story and then it becomes useless.
- you add some (really trivial) complexity to the game because people have to choose how to use their resurces (energy still needs to be more useful)
- you can still gain money from that action since players will consume energy and the paying ones can restore energy using kobans.
- players will thank you since we are loosing kobans for click errors

Or another suggestion could be that you simply delete that button.


Another use for energy that came to mind: maybe some daily (weekly!?) quests can cost energy. This could really add some resource management decision.