The novel is based on the story of Hachiko, a faithful dog who became an emblem in Japan and a symbol of friendship and whose story provided the inspiration for two films: a Japanese one from the 1970s, and the Hollywood remake starring Richard Gere from 2009. Hachiko the dog has also a statue dedicated to him in Shibuya Station (Tokyo). Lluis Prats recreates the story of Ueno, a lecturer at Tokyo University, and his dog Hachiko. After taking him into his home, the dog accompanies the lecturer every morning and waits at the station for him to return. The bond between them will grow to become the ultimate expression of friendship and faithfulness. A relationship that nothing, not even death, can break.