My gut tells me you're really going to like Enchanter if you liked Carnivorous Princess Yegrinna and vice versa. In both a non-human girl freeloads at some guys house and trolls him (one of them doesn't do it entirely on purpose though). TBH, I can really describe well why those series are similar (despite the fact that they certainly are), so just trust my gut on this one :)
If the math obsessed male lead from Carnivorous Princess Yegrinna caught your attention, you might want to check Suugaku Girl since it has another character obsessed with math (and more than one).
Both series have an animal-girl female lead and a (relatively) smart human male lead. There really isn't much else to add, but I honestly believe there is no need. Simply, if you liked one of those series, you could try the other one too.