MissRyu

So I'm new to the game and I've been playing for maybe a week now and the Dark Lord is testing my patience. I'm lvl 16 and he's level 12 now, still steady gaining levels because i keep battling him but he hasn't dropped one of his bitches a girl. I have collected all the gems and I keep fighting him, but I'm mid-save the princess mission. Is that my problem? Is he not giving me a girl because I haven't completed the whole area? Please help me, I really want the Succubus from this week's event. Thank you.