Meaning:

“爬” means “to climb,” and “楼” is short for “楼梯,” which means “stairs.” Chinese netizens use the term to refer to the scenario where a person has missed the previous discussions in a WeChat group or at a forum, and has to roll the screen up to check out earlier comments. As people’s comments build up like a tower on the screen, the term “stairs climbing” is used.

Example:

A: 同学群里有个特别热烈的讨论，你看到了吗？

Tóngxuéqún lǐ yǒu ge tèbié rèliè de tǎolùn，nǐ kàndào le ma？

There is a very heated discussion going on in our classmates’ WeChat group. Have you noticed?

B: 今天一直很忙，等中午吃饭的时候我去爬搂。

Jīntiān yīzhí hěn máng，děng zhōngwǔ chīfàn de shíhòu wǒ qù pálǒu。

I’ve been super busy today. I’ll check out the earlier comments at lunchtime.