Cake spend a lot of time on Earth since the dinosaur era to gain experiences. Later on the higher ups decided that he's qualified to guide other new born/intermediate souls, so they send him out on the guiding quest. Often time, when a mentor is given such quest, they don't have to reincarnate; unless specified otherwise.

Minoh is the current soul under his guide. Usually the Higher-ups would pick student and teacher who share the same characteristics. Minoh is very quirky but also very skeptical. She would easily trust in someone who used to be just as quirky as her, to guide her in life. Since cake can't be seen by bare eyes, dream interpretion and tarot is the only communication method he can use with Minoh. Sometimes he blinks lamp too but that would scare the others.