Here's why this works:
* Dank is used in internet slang to describe something that is high-quality, humorous, and often a bit offbeat or strange.
* In this sentence, "dank" is used to describe the meme, implying it was very funny and unique.
Here are some other examples:
* "The music at that party was dank."
* "I found a dank video of a cat playing the piano."
* "That new album is dank as hell."
Important note: The word "dank" has a more literal meaning referring to something moist or humid. However, in modern slang, it's primarily used in the way described above.