梅雨で憂鬱な気分になっているちびメカゴジラを外に連れ出したちびゴジラ。
面白いものをみせるからと呼び出されたちびギドラとちびモスラが目にしたものは雨でバグったちびメカゴジラだった。
するとちびメカゴジラが人間界にいた頃の事を話し出して…
Chibi Godzilla took his friend, Chibi Mechagodzilla, outside to cheer him up, as he was feeling down due to the rainy season.
Chibi Ghidorah and Chibi Mothra, who had been called over to see something interesting, instead found Chibi Mechagodzilla acting strangely, seemingly affected by the rain.
Then, Chibi Mechagodzilla started talking about his experiences in the human world...