Akama Ga Kill, Black Lagoon, High School of the Dead, Physhco-Pass, Rosario to Vampire, Zettai Karen Children, A Certain Magical Index and Black Blood are a few that I can think of that share similarities.
Removed Blood+ it's not for everyone, if you enjoyed Monster then I suppose you will like it too.
If you have the chance, try and watch Fate/Zero and Fate/Unlimited Blade Works. It has amazing character, story and the blended 3D CGI make Hollywood look like a back yard production studio.