The King's Secret (King #3)
Wayne Mansfield

When Pan returns to the palace after a month-long visit with his family, he stops along the way to bathe in a small lake not far from the palace. But during his swim, his escorts disappear and Pan is abducted.
Terrified, all Pan can think of is what his beloved King Seronisis will think when he doesn’t arrive home on time. He's taken across the desert to a cave where his captor lives in exile. When he discovers the reason for his abduction, he wonders how he can warn Seronisis of the forthcoming threat his abductor poses to the monarch. But how can he escape? And will he ever see his lover, King Seronisis, again?