fanservice

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Fan service

Wikipedia

• fan service

Calque of Japanese ファンサービス (fansābisu), equivalent to English fan +‎ service.

(Can this⁽⁺⁾ etymology be sourced?)

fanservice (uncountable)

1. (fandom slang) Elements added to a television program or similar entertainment that appeal to avid fans but are of little interest to outsiders.

   Synonym: fanwank

   • 2008 January, “Silent Hill Origins”, in GameAxis Unwired, page 42:

     For as much as the game is about Grady, it's also about tying up loose ends from the other games. If you're a veteran, prepare to be in hog heaven with the fanservice present.

2. (fandom slang, chiefly ACG, often derogatory) The inclusion in a work of fiction of material, especially of a racy or sexual nature, which may or may not have relevance to the storyline and is designed merely to excite the viewer.
   • 2000, Ryan Omega, Anime Trivia Quizbook: Episode 1: From Easy to Otaku Obscure (Anime Trivia Quizbooks):

     And because of that soy sauce, girls can get one of the few fanservice shots made for women in the entire history of the Ranma 1/2 series.

3. (fandom slang, idol fandom) Special interactions from idols to their fans.
   • 2022 July 21, “Moments with Mimi: K-Pop girl group Dreamcatcher knows how to make fans feel special, puts on an unforgettable show”, in The Post‎^[1]:

     Fanservice is when group members interact with fans by taking their phones, accept gifts thrown on stage and acknowledge the people in the crowd.

• fan-servicey