This review may contain some spoilers.
If you aren't looking for the usual vampire stories then this is your manga. Servamp changes some things in the story like vampires are serving humans and they aren't turning into bats, but instead of that they are turning into cats or butterflies. There are 7 servamps and each of them symbolize some kind of human attribute. ( i don't know if it's proper in english, but i mean the things like sloth, anger, etc.. )
One day Mahiru finds a black cat and he decides to take care of it. The following day the cat turned into a human in looks but actually he was a vampire. Mahiru named him Kuro and because of that they actually made a contract and Kuro became his Servamp.
The art is a little bit confusing but it not really bothers the look. In the manga the art sometimes look cute and sometimes really serious. The fights are especially good. So well done for the author and i really like the chibi looking parts :)
The characters are one of the best parts of the manga. The two main characters are totally opposite of each other.
Kuro: He is a very lazy vampire who is often called NEET in the manga because he not really likes leaving the house. He not really likes doing anything. He finds problem in anything and always trying to avoid everything. Personally i really like his character and he is so much fun :)
Mahiru: As i said before he is the perfect opposite of Kuro. He helps everyone and he tries to do everything what he is capable of and often more. He often fight with Kuro but they are really close "friends".
It's really enjoyable, unfortunately there aren't many chapters out yet, so i cannot really say anything about it in long range, but it looks interesting and i am looking for it's continuation.
It's really good manga but short, so if you have 2-3 hours of free time you should definitely read it. It will get an anime adoption soon.
So overall i liked it very much and you should give it a try too.
Thank you for reading my review and please send me your thoughts about it!