Rui knew that he probably shouldn't have indulged his urges and lust, especially in those circumstances. He was the formal ambassador of the Martial Union and the Kandrian Empire. It reflected poorly on both those organizations if he engaged in illicit activities while representing them.
Yet, it was precisely because of these circumstances that he felt deeply aroused.
Back in the Kandrian Empire, his status had reached unprecedented levels for any Martial Master, achieving a realm of political and Martial power that was extraordinarily high even by the standards of Martial Sages.
If he desired women, he could have himself an ocean of them.
Yet, all of them sought him for status as a Master, his status as the informal crown prince, his status as the diamond boy of the Martial Union. Without them, they would be gone, which turned him off. The effort it took to find a partner that wasn't primarily driven by such greed was too much.