Fan service does not necessarily implies adult content (PG-18). Remember, Love Hina is PG-13.
It broadly refers to depiction of racy contents in anime/manga to excite the viewer. The common usage of service are shower scenes, hot springs, bathing suits, pantsu shots and bouncing breasts.
On the topic, my opinion is service is not a necessity. But, if used judiciously/tastefully doesn't hurts either. Once in a while you do come across some mature themes in an anime, but the key is how tastefully it is handled.
There are many series with fan service that I like, but I am also of the opinion that many would have been a lot better without them.
I think many of us have seen it with or without knowing them. Remember
Stratos 4 Yeah! Studio Fantasia is notorious for that!
@Arr0wHeaD: Talking about pantsu flashing, you haven't seen anything till you have seen Najica Blitz Tactics. You will lose count of the pantus shots, zillions of them
And did I mention the Limited Edition artbox of the series came with a WCP
(Undergarment... ha ha!) :-"
I almost fell from my chair when I took it out of the box! o_O
But, at the same time I liked the story, so if you can ignore them you might like the anime.
