Wait

As soon as they walked out of the quarters, Seven, who had just resumed, followed them before anyone else will.

  Eva knew they were being watched and followed; she needed an excellent opportunity to move closer to the Queen to repeat the instruction that Eight had told her.

  According to Eight, as long as Ellen desire to be like the maid who has taken the content in the bottle, they could both change appearance.

  This means Ellen will look like the maid Marian and Marian like Ellen. Eva was unsure how the necklace would work; she did not know if it would take just a moment or an hour, after all, the Steward did not allow her to finish the conversation with Eight earlier, so she needed to watch the two and not leave the palace with the wrong person.