二枚目

The literal sense is a compound of 二 (ni, “two”) +‎ 枚 (mai, counter for flat things) +‎ 目 (me, ordinal marker), literally “second sheet, second flat thing”. The idiomatic usage arose from a convention during the Edo Period wherein a kabuki play's handsome character would be listed second on signboards.^[1][2]

• (Tokyo) にまいめ (Odaka – )^[2]
• IPA^(key):

二(に)枚(まい)目(め) • (nimaime) 

1. Used other than figuratively or idiomatically: see 二,‎ 枚,‎ 目. (the second sheet or other flat thing)
2. a handsome male character, especially one that gets involved in a romance during the story
3. (by extension) a handsome man, a male love interest

• 二枚目半(にまいめはん) (nimaime-han, “a comic character who is also the male love interest”, literally “second-and-a-half sheet”)

• 三(さん)枚(まい)目(め) (sanmaime, “comic character; antagonist, bad guy, baddie”)