@lustmord : Gently head-bonks him.
Admittedly, he was distracted. Such that Lucius managed to enter the grand salon and approach, surreptitious in his mischief, whilst he noticed nothing until it was too late. In his defence, Antonín's attention was hopelessly captured by the current spectacle: a musical performance for his eyes and ears only, which in turn demanded full sensory engagement.
The singer's sublime voice seemed to both harmonise with and fight against the rapturous violin, challenging each other to conjure impossible notes like an intertwined spell of enthralling magic. A rather unnatural feat this was, for the woman's vocal cords were altered to sing like no human could, a thick choker of pearls and gemstones concealing the gruesome scar across her throat. Likewise, the man's hands bled to move faster and more precisely, utilising the same arts that drained the life of those who wielded it as a weapon.
Both violinist and lyrical diva cease their inhuman musical display at once, staring at the bold Knight in mirroring horror. Antonín stares at him, too, eyes open wide --- snapping out of what was almost a trance.
And yet the Prince merely laughs.
"Are you a feline now, Knight?" He's more or less used to Lucius' antics by now, having decided that there's nothing particularly harmful about them. For the most part.
"Sit with me." No room to reject this generous invitation, as he gestures towards the consternated musicians. "The Lady Evelyn and her brother have composed several new pieces --- all of them positively exquisite."