Gossypol, from cotton seed. Inhibits sperm production, may not be reversible. Reproductive Technologies . Miracle of Life. Check out the excellent video, Nova - Miracle of Life, available in the library.
Asexual reproduction is particularly common in plants and a few animals.
Sex is not for pleasure. There is little foreplay in most species and orgasms are rare in other animal species. Sex is risky business. Sex is not selfish. In other words, the result of sex is offspring that have different genes than their parents.