In a species that reproduces sexually, sexual attraction is an attraction, usually, to other members of the same species for sexual or erotic activity. This type of attraction often occurs amongst individuals of a sexually-reproducing species, although in many species it serves no immediate reproductive goal – indeed, some sexual behavior among primates is undertaken as a social activity.
Certain aspects of what is sexually attractive to humans may differ amongst particular cultures or regions. Influencing factors may be determined more locally among sub-cultures, across sexual fields, or simply by the preferences of the individual. These preferences come about as a result of a complex variety of genetic, psychological, and cultural factors. The sexual attraction of one person to another depends on both people. Much of human sexual attractiveness is governed by physical attractiveness. This involves the impact one's appearance has on the senses, especially in the beginning of a relationship:
As with other animals, pheromones may also enter into the picture, though less significantly. Theoretically, the "wrong" pheromone may cause someone to be disliked, even when they would otherwise appear attractive. Frequently a pleasant smelling perfume is used to encourage the member of the opposite sex to more deeply inhale the air surrounding its wearer, increasing the probability that the pheromones from the individual will also be inhaled. The importance of pheromones in human relationships is probably limited and is widely disputed, although it appears to have some scientific basis.
Many people exhibit high levels of sexual fetishism, and are sexually stimulated by other stimuli not normally associated with sexual arousal. The degree to which such fetishism exists or has existed in different cultures is controversial.