Concrete Garden

A bunch of hard sci-fi stories. 1st story - Concrete Garden Angels exist and Kashii Kiyoharu, grandson of the man who "created" the angel, has been hired to befriend him. His name is Toki. Kashii soon finds out why the scientists need him around. Toki is lonely, but no one wants to get near him unless it's necessary since he eats human flesh. What has Kashii gotten himself into? 2nd story - Clock Down Everyone expects Tokiwo to go to a good university. However Tokiwo doesn't want to in order to "play it safe". One night there was suddenly an earthquake. The stone he was looking at started to glow and out of his floor comes someone who looks exactly like his childhood friend Jiu. Well there is a difference. This "Jiu" is dressed for combat and has a very large weapon. Just what does the stone have to do with "Jiu" and who gave Tokiwo the stone?