Meaning:

“是” means “is,” “个” is a quantifier, and “狼人” literally means “wolfman.” This saying, coined by Chinese netizens, is a play on words, as the character “狼” (wolf), has one more stroke than the character “狠” (hěn, meaning “tough, ferocious”). Roughly translated as “she/he’s a genius,” it’s often used jokingly when someone comes up with a wild card kind of solution to a problem that actually works.

Example:

A: 听说丽丽的男朋友经常干家务。

Tīngshuō lìli de nánpéngyou jīngcháng gàn jiāwù。

They say that Lili’s boyfriend takes care of some household chores.

B: 以前也不干，后来丽丽陪他打游戏，但是输的人必须干家务。

Yǐqián yě bú gàn，hòulái lìli péi tā dǎyóuxì，dànshì shū de rén bìxū gàn jiāwù。

He didn’t do housework before. Lili plays computer games with him, on the condition that the one who loses a game has to do some chores.

A: 这小姑娘是个狼人。

Zhè xiǎo gūniang shì ge lángrén。

She’s a genius!