Orgasm, or Denial?
Over the days that follow, having plenty of time on your hands, with hindsight you are able mull over the series of events that led to the queen's discovery of your nocturnal engagements with the princess.
On the evening prior to that which culminated in your imprisonment, you had scoped out a merchants' warehouse, laying the groundwork for a future planned goods "exchange". Experienced an adventurer as you are, this should have been child's play, but ever since the beginning of your relationship with the princess, you've been in such a constant state of arousal, that there are moments out of the blue, where, unbidden, you gasp in response to a sudden surge of desire within your groin.
One such moment occurred that evening in the warehouse, and you believe that someone heard that utterance. While your rogue's instinct told you to go to ground and listen carefully, the arousal seemed to override that instinct—like there was a part of you that wanted to get caught. Looking back, it's now clear to you that you were followed from the warehouse to your later rendezvous at the palace, and that that information was sold or traded to the queen's network of spies.