Her demon lover was gone and her body covered with a sheet.
I have killed her lover, yes, killed my wife's lover.
Though she concealed from him her intention of keeping him under her wing, Petya guessed her designs, and instinctively fearing that he might give way to emotion when with her--might "become womanish" as he termed it to himself--he treated her coldly, avoided her, and during his stay in Moscow attached himself exclusively to Natasha for whom he had always had a particularly brotherly tenderness, almost lover-like.
In fact, he wasn't much of a lover at all.
The mention of Arthur and the Round Table at once brings him to mind as the most valiant member of that brotherhood and the secret lover of the Queen.