You should prompt the player to check the girls by clicking on them. I had to experiment to know how to upgrade them and make the game less tedious because of the lack of fast forward or "close early" function, making me feel like I've wasted my time.
Edit: It seems that the speed controls don't react properly to mouse clicks. Might want to make a bigger button with a larger hitbox, an all-inclusive "speed" button that tells you how fast it's going.
Edit: This was explained in the beginning tutorial, but I think it shouldn't be so massed and instead an "as it's needed" optional tutorial. You might want to give "massed learning" or "do you want prompts as they become relevant?" option.