It's usually in the form of a Reverse Harem, but it can also be used in regular harems.
But instead of all the love interests loving the protagonist, everyone hates the protagonist!
A genre in manga and anime where a single (often ordinary) girl is liked and followed by a bunch of handsome men (3 or more) who are all madly in love with her. The girl often cannot pick which guy she should go out with and remains indecisive.
A genre in anime and manga that every weeb indeed watches, however it is never discussed among fellow weebs.
A harem is essentially when there is a boy who is bombarded by a bevy girls presenting various physiques. The girls in the harem are all attracted to the boy and often fight over his affection. A Harem can be metaphorically describes as a rooster in a henhouse.
A man who is surrounded by girls but can never choose which one to marry or which one to be his girlfriend. Typically is a male who goes to a Japanese school and either is awesomely smart, extremely kind, or just a badass.
Player 1: Hey dude, is it just me or does {Kirito} have a lot of babes with him?
Player 2: Yes he does, he has now been crowned the Harem King of {Sword Art Online}
Player 1: Aw man, how do I become a Harem King now?
Player 2: You either do everything you can to attract girls or become a {Kirito}.