Overstimulate was correct and Pompoir is correct
My reasoning was as follows:
1. Orgasm - Contractions of the vaginal muscles needed for pompoir also happen during orgasm
2. Protein - needed to build muscle, and pompoir is used to strengthen muscles
3. Muscle - self explanatory
4. Immerse - I was thinking along the lines of a vagina 'immersing' a penis due to the contractions
5. Rough - The texture of the vaginal walls as felt by the penis can be described as rough
6. Overstimulate - pompoir can be used to overstimulate a penis during or straight after orgasm
7. Pressure - I imagine a penis would feel pressure due to the contractions and squeezing around it
Well done all! Some of the images may have been a bit too hard but we got to the right answer with some fantastic teamwork.