Bloom of Youth Hundred Years Friendship

Mace who is a friend of Shiyi and Senhan mysteriously disappears in a party for them. Shiyi and Senhan have never given up to look for him for several years.Shiyi finds a space-time watch by accident. Shiyi and Senhan mysteriously come to a hundred years later after starting up the space-time watch and meet the space-time human trader who used to abduct Mace before.They accidentally find that the reason why the human trader to abduct Mace is to save the world for centuries later.What's wrong with it?What will happen in the future world?Shiyi and Senhan do not hold back. They determinedly come to the future world...Can they find Mace?Can they rewrite their previous friendship?