Female koalas have become infamous for engaging in lesbian sex. Females often overlook males and participate in sexual acts with other females, sometimes in orgies with up to 5 female koalas. This behavior has only observed in captive koalas though, who surprisingly engage in only one heterosexual mating act for every 3 homosexual mating acts. There are many theories as to why this occurs, from ‘turning the males on’ and to relieve stress. The most probable one though, is an impairment of hormones in captivity. In sex society term “koala sex” is when male is overly aggressive to the female. Holding her from the back and pushing her face down. Maybe this is why female koalas mate with each other.