This is a draft I wrote ages ago that I just discovered. I hope you find it interesting. If you think of anything i might have missed lemme know :)
1. Shower sex...not as easy as it sounds unless the girl is tiny and the guy is strong enough to pick her up and support her weight. Also issues with slipperiness. However experimentation can result in a few positions that are manageable for a few minutes at a time....
2. Timeframe. RN have these whirlwind romances that would honestly freak me out if it happened in RL, If we fell in mutual love in the space of a few days i would be terrified. Something that burns so hot initially is bound to burn out.
3. Strong hatred turned to love. Yeah right, admittedly some of the most passionate anger can be a disguise for lust but really strong feelings where the person has been badly hurt by the other person cannot be changed, especially in such short spans.
4. Multiple orgasms. The girl is often uptight or reserved in the beginning before being unleashed, turned into a sexfiend. Both partners can orgams repeatedly in a session of sex, everytime. In almost EVERY book this occurs. Frankly there is a large percentage of the female population that can't orgasm, or struggles to multiple.