Back in junior high, Ami had once solved the problem of loneliness by brainwashing her entire school class to adore her. So she wasn't particularly in a position to lecture about this basic concept, even if she'd eventually grown away from it. She certainly still knew the feeling of wanting someone all to herself, looking only at her. What else had everything towards Usagi truly been about? (What else would prompt her, across dreams and the multiverse, to take John before Halsey could, or to keep him at Mariner Castle, no matter how she'd insist it was for his own good?)

However, if Cortana ever hurt John, Mercury would not hesitate to end her. John was the more important. Mercury needed that calm assurance, and that goodness that fascinated her as much as it confused her. She needed them more than anyone.]

And who else could Cortana mean? It could no longer be ignored.

"Could it be you mean John?" she asked bluntly. "I won't let you harm him in the meanwhile." A flat, definite statement. There were certain things this rampant AI had better get clear from the start.