i tried to explain it to them , but when i got to the part about the real orbit of the moon and the apparent orbit of the sun , i lost them . her odd little half smile appeared at the mention of his sister . he tossed me a package and kept on going until he disappeared out of sight , into the forest . i know you did n't want us to stay together , but ... '' oh , god . always difficult to guard against vague threats . `` you have always been my very best friend . 