Lionesses aren't too hard to come by. With events like them suddenly appearing, and frolicing with the young wandering cub is nice. But... maybe when your impression progress gets to a certain rate, maybe the ladies come to you rarely? Like, admiring lionesses? Some of these gals (the female lionesses in general) are hard for beginning players to conquer; At least they were for me when I just began. I suppose thats what the IMP is for, but still. Maybe a 1/100 or 1/1000 chance of wandering that a roaming female will come towards you and find you somewhat appealing? (If anything to make claiming them a little easier)