"I didn't want to write an all-out sex song... I just wanted to write something that was fun and hinted at sex"- Bill Danoff, writer of Afternoon Delight.
Hinted? Give me a break. "Rubbin' sticks and stones together makes the sparks ignite" is not a camping tip from a Boy Scout Manual, nor some metaphorical allusion to a bit of a cuddle; neither even to a casual wristy nor a post-lunch knee-tremble. This, people, is a blatant reference to bumping uglies. "Skyrockets in flight"? Hurr hurr snerk snerk!
The full post is on Perfect Sounds Forever.