It is Eros who is responsible for mortals falling in love with one another according to the Greek mythology.
The prevalent myth suggests that Eros was born of the commingling of Venus with Mars a nice summer evening. As a true son of the Goddess of beauty, Eros was the god of love, lust and sexual activity. According to all the Greek myths, Eros was beautiful, but also a constant source of trouble for both gods and mortals.