SpoilerHe is, in fact, a clone created by Aoyama Pharmaceutical company. The original Kōki Maeno died during an experiment that involved his vivisection. His memory lacks realism as it is actually the memory of the original Kōki written into the clone's brain by artificial means. After discovering the truth, he chose to keep living and began working at Asōgi Consulting, where he spent the next twenty-one years. Some time between episodes two and three, he married Yuki Shimazaki and had a son named Teruki with her. In episode three, he is shot by Sayara while rescuing Rin, and has to consume a time spore in order to survive as an angel. After saving Rin and having one last tender moment with her, he returns to consume Sayara, but is killed by Eipos before he can finish. His time spore, which had previously infected Yuki's brother, is lost, however, it could be the one Rin found in the sea in episode five.