In early summer, most parts of Japan get visited by a rainy season, the so called Tsuyu (梅雨, also pronounced Baiu), literally meaning « plum rain », because it coincides with the season of plums ripening.

Japanese has a very large number of terms to describe sounds, and in particular a much larger amount of onomatopoeias than many languages, including English. « Onomatopoeia » comes from the Greek onomatopoiia which literally means « word created to imitate sounds produced by living beings or objects ». In Japan, the use of onomatopoeias goes far beyond the reproduction of sounds (Giongo, 擬 音 語), since some of them refer to a physical or emotional state.

To the Japanese ear, Potsu Potsu (ポツポツ) is the sound of raindrops starting to fall on dry ground. For english ear its Pitter Patter or in french Plic Ploc.