I'm a lover and only have "charm" girls : Kimie and Sung tai ki. Plus Agate and Jennie. Maybe the drop rate for the "charm girls" for lovers (I mean charm->lover, Hardcore->shagger, Know how->Expert) is "good" ... not bad ... not the worse ... anyway. And the drop rate for "other type" girls is just about 0.0000000000000000...01 or something like that.

On other side, I play since september so I can only say I haven't received any girls since ninja village.

youre just unlucky or i am lucky
free player with 13 girls here (gruntt currently only drop 1 girl 13=max)
keep farming
Kk. And you are Unregistered too. Everybody can say "I got allll the girls WITHOUT paying !" without that being true. Nevermind. I'm just mad ^^