Amnesia Concepts

Mental condition of when someone forgets almost all of his or her past, including his/her identity. Some anime characters have such an allingment.

The character has known the protagonist for a long time, typically all his/her life. If he/she's from the opposite gender there's a high chance he/she has a crush on the main character.

If a "harem" anime features one man surrounded by female love interests, a "reverse harem" features one woman surrounded by male love interests. Prototypical reverse harems: Ouran High School Host Club, La Corda d'Oro, Fushigi Yugi.

The term generally used when anime is broadcast--usually online--in countries outside of Japan around the same time as it airs in Japan, usually within one week or even within 24 hours.