Kazuki attends Aoi Academy and is a below average person.  He lives in a world where magic can occur and each person has a limited number of spells they can cast.  He can only use magic eight times before he will turn into dust.  Because he has so little magic, no one really associates with him that much.  Then, suddendly, three young girls show up wanting his genes.  He is evidently from a line of famous magicians and, although he has little magic, the chances are good that his children will.  Now he must deal with a quite young girl who calls herself his wife, a more forceful girl who just wants to get the job done and get out and a girl who doesn't like her role at all and wouldn't mind killing Kazuki just so she can get out of there.