The anime is pretty much "Fan-Service", but the manga has a plot and the "Fan-Service" is few... Well, fewer than the anime.
Personally I see the "Fan-Service" in the manga as filler to to the story, seeing as how the story is about a human in a school for monsters that would kill him if they found out he was human. Only one person knows he's human and that's Moka... The girl that he likes. He even decided to stay at the school for her. The rest of the story starts getting good about chapter 20, that's when Tsukune starts having a reaction to the overconsumption of vampire blood in his system. After that the story starts to go a lot faster and the "Fan-Service" takes a back seat to the story much moire than before.
I would suggest reading the chapters leading up to Chapter 20 though as they introduce a lot characters that are pivotal to the plot later on in the manga.
Personally I see the "Fan-Service" in the manga as filler to to the story, seeing as how the story is about a human in a school for monsters that would kill him if they found out he was human. Only one person knows he's human and that's Moka... The girl that he likes. He even decided to stay at the school for her. The rest of the story starts getting good about chapter 20, that's when Tsukune starts having a reaction to the overconsumption of vampire blood in his system. After that the story starts to go a lot faster and the "Fan-Service" takes a back seat to the story much moire than before.
I would suggest reading the chapters leading up to Chapter 20 though as they introduce a lot characters that are pivotal to the plot later on in the manga.