露珠湿沙壁

Meaning

A substitute characters for "令人作呕" (nauseating/disgusting). Refers to someone or something being so disgusting it makes you want to vomit. Originated from mishearing "丑" (ugly) as "吃藕" (eating lotus root). Since then, most common characters with the "ǒu" pronunciation have been split into "藕" (lotus root).