Fushigi no Maria-kun

First off, don't expect anything much deep in this manga since it's funny, charming, and childish filled with minor obstacles here and there kind of manga.

The female lead, is a kind, loving, naive, and hot-headed character who befriends the male lead, who is a vampire when they were five. Due to her, he is accepted in the human world and does a lot of charitable things to maintain a good reputation in society.

The characters (their classmates, parents, etc) who ship the couple are fun, the villains have motivations of their own to either sabotage him and kidnap him. The girl is oblivious to the romantic feelings he has and we see how she always steps in or puts herself in danger to protect him.

The story develops as we get to know more about the history of vampires and the abilities they possess. Not much of a surprise there. The adults also play an important role in this due to the difference in opinions and rivalry between them. (which is almost comical)

The art is quite attractive and appealing in a "shoujo" way.

I enjoyed the manga a lot even though it seemed like it abruptly ended when it could have shown us more, don't be disappointed with the progress of the couple too much, folks xD