Unlocking the Second Ending
To get the second ending, you must unlock The Hidden Truth Story Entry. There are three parts to this story entry, and all of them are found in the same room, the Consort Jade boss fight. One of them drops from Consort Jade when she is killed, the other two can be found by destroying furniture in her room. Keep in mind that you must unlock the story entry in the starting area. Collecting all three objects without unlocking The Hidden Truth will not unlock the second ending.
To get to her boss fight, take the left route in the plaza with a crane, tiger, pig, and turtle statue. The right route will take you to the corrupted tiger guard instead.
After Unlocking The Hidden Truth
Spare him and proceed through the game as usual. Defeat the last boss, and hit “destory the throne”. If you spared Qin Wu another prompt will appear. Select the “Blood” option.