A reverse harem includes three or more characters who potentially show romantic interest in a female protagonist. The sex, gender, or orientation of the harem members is irrelevant as long as they exclusively, or at least primarily, are vying for the affections of the same individual - who may or may not reciprocate towards one, several, or none of these romantic rivals.
These anime showcase the joys and hardships of falling in love, whether a schoolgirl has an unrequited crush on her senpai, a Love Triangle occurs within a group of friends, or rivals become lovers through competition or their intense passion for each other.
Shoujo (少女), translated as "young woman", is a demographic aimed at teenage girls. The most iconic and influential Shoujo character designs come from the early 20th century, where girls and boys alike were drawn with huge eyes. Shoujo is the counterpart of Shounen, a demographic aimed at boys and young men.