Argonaut octopus males detach their sperm-storing arm during mating, which the female carries off.
Dolphins have sex for pleasure, engage in complex social sexual behaviors, and even use objects to get high.
Flatworms engage in 'penis fencing' to avoid being the one to carry offspring, a battle of reproductive duties.
Male giraffes taste the female's urine to check for ovulation before engaging in a slow courtship ritual.
Bed bugs practice traumatic insemination, where males stab the female's abdomen to fertilize her.