Tokyo, May 31: Akihito Emperor, the granddaughter of the Princess Mako, arrived on Wednesday in a nine-day trip to Japan.The 25-year-old princess, the eldest daughter of Prince Akishino, second son of the Emperor and second in line to the throne, is expected to arrive in Bhutan on Thursday after a brief stop in Singapore, reports Efe. This is her third official overseas trip and comes just two weeks after the announcement of her engagement to a college friend, 25-year-old legal assistant Kei Komuro. Mako will receive a welcome ceremony in capital Thimphu and will later meet Japanese volunteers in the country. She also visits a flower show in Tumfu and travels to Takhtang, the iconic Buddhist temple in the Paro Valley.