The Fandom Post is reporting that Tubi TV has added four seasons of the Natsume’s Book of Friends anime to its service. The episodes are available to users in the United States and Canada with the original Japanese audio and English subtitles.
Natsume’s Book of Friends is described as:
Natsume’s Book of Friends follows the story of high school student Takashi Natsume, who possesses a strong ability to see spirits. He inherited this strange ability from his grandmother and has had it as long as he can remember, which has made him introverted and shy. His life changes one day when he receives a mysterious book that belonged to his now deceased grandmother—the Book of Friends. Takashi soon discovers that the book is filled with the names of countless spirits that were sealed away by his grandmother. Not only that—the spirits who have their names written in the book must obey any order given by its owner. As a result, the book becomes a prime target for all roaming spirits trying to gain control of the spirit world.
Source: The Fandom Post