Kaibutsu Oujo, Rosario to Vampire Recommendations
Harem, vampires, wolfman, and other monsters all in both
Both are fun harems that revolve around irregular monster girls.
Both are hilarious and use a lot of simple sophomoric humor that'll make the child inside of you laugh out loud.
Both feel kind of episodic and light.
Both have great fan-service, not too heavy that they have to abandon the story, but not too light that it's not satisfactory; it's the perfect mix between plot and "plot".
Both DO have a good amount of battles and action but do NOT depend heavily on them like most newer harems; therefore, are more of slice-of-life and less of action ones. Even the battles are so simplistic and easy to follow