Board Thread:Theories Discussion/@comment-24391560-20150117235044/@comment-6192846-20150118024113

The line is in complete reference to the Golden Key. The full interchange is roughly:

MotC: [...] only one vessel remains. If you know its location, then testify, Mage of Time."

Ma: "Passing through time, changing form, changing owners, it has already appeared on the stage. Even so, I don't know its current whereabouts. It's probably in the hands of that girl."