The Priestess' Bridegroom

King Rediva had summoned the Rhodian Centaurs to help in the war against the Unicorns' Peace Empire.
However, the warriors unexpectedly meet the most beautiful mare of all time and fall head-over in love with the beauty.
Now, this mare is, of all things, one of the highest-ranking priestesses of the Black Unicorn, the king's enemy in the flesh, and also enjoys a very high reputation among the unicorns.
Nevertheless, the centaurs set off to dare to show up before the Lord of the Order and ask for the mare's hand. This one, instead, sends them on a murderous quest.