The inclusion in a work of fiction of any material, especially racy or sexual material, which has no relevance to the storyline, but is designed merely to excite the viewer.(noun)
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Use "fanservice" in a sentence
"Thankfully, the most egregious fanservice is simply Nami in a bikini."
"A few things which are commonly termed fanservice in the anime fandom are pantyshots, meido (maids), nekomimi (catgirls), meganeko (girls with glasses), boob shots and gothic lolitas."
"From the anime’s OP sequence, you’d have obviously seen how much fanservice is waiting for you when you actually watch the episode."