If you're looking for similar to Letter Bee TV, you might like these titles. All recommendations are made by Anime-Planet users like you!
Natsume is lonely; he has an ability that separates him from others: he can see and interact with spirits. Soon, however, Natsume discovers that he’s not alone: his grandmother Reiko also had the gift. But things get hectic and possibly dangerous for Natsume when he finds out that he also inherited the 'Book of Friends', a book that contains the names of all the spirits Reiko defeated and subjugated. He finds himself hounded by his grandmother's underlings and, with the help of a 'cat' charm spirit, decides to free them from the Book's shackles, as well as protect the book from those who seek to misuse its power...
Nai’s friend Karoku is missing, and the only clue to his disappearance is a mysterious bracelet. One day while travelling, a young thief named Gareki saves Nai from a monster and takes an immediate interest in the trinket he carries, as it is the insignia of Circus, an elite group who travels the world capturing notorious criminals. Together, the two decide to track down Circus and see if they’ve taken Karoku, but luckily, the group finds them first. Unfortunately, they have no idea who Karoku is or why he had one of their identity bracelets, but in the hopes of getting to the bottom of the matter they offer their assistance. Now, Nai, Gareki and their new friends set forth to find Karoku, but with more questions piling up each day will it be possible to achieve their goal?
A young boy with white hair and special abilities who isn't exactly human but takes the form of a human and is searching for a friend they care deeply for is the main character in both these anime. Both characters join or sort of join a government agency to find the friend they lost. Both include themes of human and animal experimentation, special powers, before the invention of phones (although Karneval has a similar device), and is set in a different world.