Nasty Freeloaders

Have you noticed that many magic tools such as giant Doomsday clocks or portals to other dimensions require Celestial Mages to function? Zeref did. That's why he decided to send his dragon to one too. So now Lucy Heartfilia is hosting Acnologia in her body. Well, crap, this is bound to cause some problems. Some crackfic elements. Almost total OOC. Rates T just in case.