And that was because Wiseman forced him kill Saphir and revealed that he was just a tool.
So his first goal was to kill Wiseman, not Sailor Moon.
Do you know why? Why did he want to conquer NQS and felt so pissed off about her gaze?
Because he knew that deep down, she was right about him. He was a monster for doing so, but he tried so hard to deny that by using force on NQS and Usagi, to conquer them to show that he was right. But he had to accept it.
Even the manga showed part of his thoughts and struggle here.
Manga Demande was a interesting character, and it's more about is he good or bad, but his fitful ending.