Maria is glad she gets to see Lucifer again, believing that she's an angel, and then has her heart stolen by the Demon King. Lucifer forces Maria to follow her and lets her live a life of luxury. Meanwhile, Leviathan, who has strong feelings for Lucifer starts to get jealous over Maria because Lucifer won't pay any attention to her.
I have to obey Onee-sama.
Ich muss Lucy gehorchen.
Tengo que hacerle caso,
Tengo que obedecerla,
Je peux pas me permettre
que tu ailles cafter à Lucifer,
Devo obbedire agli ordini della Mia Signora.
Tenho que obedecer a Onee-sama.
Я не могу противиться воле сестрицы... 
так что я просто сведу тебя с ума.