When the rumors about a demon named Marie, is trying to replace you, and lie by saying she's the Descendant of Solomon, it piqued the Seraph, Michael's interest, but not in the way you think of. He likes you, so this angers him because you're the Child of Solomon, not her

Marie was trying to get Michael's attention, but he's not stupid. He's irritated by this brat, but he can't kill her with you by his side! "Silence, I have no time for an insignificant being like you..."