Gods of the Jungle by Nelson S. Bond

After that, the tide of events welled almost too fast for Ramey's comprehension, certainly too fast for his peace of mind. Again -- as on the opposite shore, but this time grimly, tightly -- he found himself imprisoned by the powerful arms of Videlian soldiers. He was aware of tossing a mute, apologetic glance in Sheng-ti's direction, and of seeing the old Buddhist bow his head, hearing the _bonze_ mutter, "It is the Will of Him Who watches. You could not have done otherwise, my son."

Then the Lady Rakshasi herself, a great, golden panther with eyes glinting triumphantly, was before him.