It's implied by the end of Symphony (and flat out stated in Konami's own official manga -- "fanfiction" written by Konami, basically) than Maria and Alucard hooked up. They aren't together now, though, which just gives them some character color I can play with.
 
    

When evil spreads across the land, and darkness rises and the monsters roam. When the creatures of the night make beautiful music, and the things that go bump in the night go bump with greater enthusiasm. When the world is in peril and is in need of a hero...

These guys are, sadly, the best the world can hope for. These are the adventures of the heroes of CVRPG. They mean well, they try hard, and occasionally they do the impossible...

They actually do something heroic.