As per my post in Gamcore, here's a few ideas for you to consider.
The main one, is to change your mini-game controls. Your timing game, might be more interesting. If you changed it from hitting the center circle. To two targets, on opposite ends. The idea being the game is reflecting the timing of the character. The game can be rotated depending if the action is L-R or U-D.
When it comes to controlling a character, like during the sex scene on the beach. I found the idea of timing just one direction, a little distracting. A suggestion might to change the control to both directions. Placing the game rather on the side of the screen. Super impose it, over the female characters torso. With the range of the control, reflecting the range of the character. In other words. The player would have to time correctly, the movement of the mouse. From the top of the females chest, down to the groin of the male. Then reverse the course. The timing would be based on the up/down of that action.
It would allow the player to focus on the animation, rather than having to look to the side, to make sure they timing prompt appears.
Something that might be more appealing to a game player. Is to change the highlight effect Like when the character is look for a books. Use an aura effect, rather than a particle effect. For example, when the player highlights the book. A dark light bulb appears, and keeps glowing brighter, until the character responds. When the guy on the beach disappears. Similar idea. For example. The character starts to fade, gets misty, then dissolves from the screen.