I bought the 1 slot memory upgrade for the 2k in game cash, and the next slot increased to a cost of 2.5k.

Also there is currently no way to get diamonds in the game without nutaku gold.

There is a quest button, but that just brings up the store button.

You'll spend all your time grinding cash in this game. Your XP level is used to meet the requirements to unlock girls, but is otherwise meaningless.

It feels like an unfinished game to me.