Shin Megami Tensei V Vengeance - Demi-fiend (Hard) (No NG+)

I saved all my incenses during the entire playthrough and spent them all just before this fight.
All the STR incenses to Masakado.
All the Magic incenses to Konohana.
All VIT incenses to Konohana.
All Agility incenses to Masakado.
All Luck incenses to Masakado.
Half of HP incenses to Masakado, the other half to Konohana.
All MP incenses to Masakado.
Even so, I got EXTREMELY LUCKY at the end.

[@Fragmaster01]

Nice clutch finish.

[@Kwame_Baroown]

How did Demi Fiend not attempt to cast Mediarahan at half health?