Frederick Florin, Getty Images

The latest trend in Japan is hamster butts. Two books dedicated to nothing but hamster butts have sold 40,000 copies already. It is what it sounds like, pictures of nothing but the butt of hamsters.

It’s called Hamuketsu which translated means hamster buttocks.  The first book was released on March 12th and sold 7,000 copies, a second book called Hamuketsu-So Cute You Could Faint came out on April 19.

According to one book buyer ‘the pictures help soothe the heart’. Believe it or not there is a difference in the male hamsters and the female, the male seem to be more popular because their buttocks are rounder and fuller.