躲在青皮西瓜后面的小太郎
[duŏ zài qīng pí xī guā hòu miàn de xiăo tài láng]
‘躲’ means hiding, ‘青皮西瓜’ refers to a green-skinned watermelon, ‘小太郎’ sounds like 'a little lad'. Imagines someone named 'Little Taro' hiding behind a green watermelon; likely a whimsical expression.