"You see, even though I am wearing a nightgown and all... Your eyes never went past my neck. Heck, you didn't even look at me as if you didn't care," Princess pointed out with a mix of playfulness and mild.... annoyance?
Although she mentioned it, Aether's gaze had never been lustful or suggestive; it was more of admiration for Empress and Delphine's beauty. Even Empress and Delphine seemed to understand this, which is why they never made a fuss about Aether's shy glances as if he had a crush on them... they almost found it endearing rather than disgusting.
If Aether were aware of their thoughts, he might have preferred not to face them again!
'I want to die...' Aether thought, not in a literal sense, but rather expressing his deep embarrassment but then, 'I will do it next time very carefully!!'... He was the Man of Culture!!