Ok picture this it is 23:00 in the real world and it's the 31st of January in the game. Naturally I decide to give it a go and try to beat Nyx. 
 
The first Strega member goes down quickly and the second one follows shortly after. It's now midnight in real life as well. Well that went quite well I thought, I give Nyx a go as well. So I save and go up.
 
First attack takes away almost a third of his health bar, well this can't be right there has to be a catch and of course there was. 
 
So it is now past 1 AM and Fuuka tells me that this is supposed to be his final form. So I attack -> 150DMG -> *blink* Did the healthbar move at all? So a long battle of attrition starts. I manage to keep alive and get his health bar to well almost nothing. This is where he starts to use Night Queen, the attack hits my fully prepared party who just received a Soma to prevent any mishappenings at the last moment. Ah ok so some members are fearful and ow is Yukari charmed? Yes Yukiko is charmed. Yukiko decides, in her charmed brain, that it is a good idea to cast  Diarahan on Nyx... Ah so he has 6000 health, well that's nice.
Not wanting to let the game beat me I go on as nothing has happened.
 
After a (long) while I'm back at the Night Queen point. It was now 3:15AM and Yukari was charmed.
 
 

I decided that  Nyx could destroy the world and I went to bed. Maybe I should have killed Ryoji when I had the chance.