Kids often make friends easily — and lose them quickly. The boy who was your best buddy yesterday has today found a new friend, a new crowd, a new world that doesn't include you. He has moved on — and you're just part of the receding scenery.

But as Ryuichi Hiroki's new film, "Kimi no Tomodachi (Your Friend)," shows, a childhood friendship can also last a lifetime, in memory if nowhere else. Based on a novel by Kiyoshi Shigematsu, the film examines various sorts of friendships, but its narrative core is a relationship between two girls that begins from conditions neither of them want, but becomes as essential to them as air.

Hiroki, who started his career three decades ago making "pink" (soft-core porn) films, observes his characters' lives in a small provincial town, from the beauty of the open sky to the casual brutality of school rivalries, with a distant but perceptive gaze. He has little use for the commercial formulas of the seishun eiga (youth film) genre, be they melodramatic plot turns or loud J Pop obliterating the dialogue.