Gonna try to make sense of what is happening during the h-scenes.
Rena got her stats on the left which are:
- The heart (fills till orgasm)
- EXPoint (numbers of orgasms... dunno about relevant. Maybe GameOver after certain amount?)
- Estrus (fills over time during sex and does not reset naturally; higher estrus causes faster orgasm I believe, kinda like Ecstasy in old HotB)
- Frustration (makes it harder to suppress orgasm when heart fills; raises after each suppressed orgasm and resets to 0% after orgasm)
The enemy got 3 bars which I believe could be called "Force" (seems to influence how fast/hard he goes, maybe makes it harder to reduce "Grip"?), "Lust" (his own orgasm-meter I believe) and "Grip" (how tight he grips Rena, influences escape-chance).
When your activity bar fills during sex you got 4-5 actions. The first 3 seem to influence "Force"/"Grip" in some way and are most likely meant to prepare escape-attempts and the 4th attempts an escape. Sometimes a 5th action appears but that does not do much, I think? At least it requires no input.
Whenever the heart is full you got two options. The first attempts to suppress the orgasm (gets harder with higher frustration; above 60% is almost impossible) and the second just lets it happen.
Of course that's just from a few minutes of experimentation, don't take anything for granted.
In any case I really like that system so far! It makes the H-elements of combat much more relevant and engaging (heh..) instead of being either pure defeat-rape, infinite-loops or super-easy to get out of as they were in old HotB.