Would someone be kind enough to explain me this joke?
This is from the TNG episode "Darmok", where Picard was stuck on a planet with the captain of a vessel whose language was all based on metaphors. So instead of just speaking plainly they recited stories in their history as part of their language. The universal translator would translate the words the alien spoke, but couldn't translate or explain the metaphors the language used.
So basically Picard had to figure out what "Darmok and Jalad at Tanagra" meant.
From Memory Alpha:
It seems that Darmok and Jalad were two legendary travelers, strangers who faced and defeated a common enemy on the island of Tanagra. Picard realizes that Dathon knew of the creature on El-Adrel IV and brought them both here so that they could re-enact the events between Darmok, Jalad and "the Beast" at Tanagra.
I guess this joke is supposed to mean that they hooked up at a party instead of the "enemies becoming friends" part of the original story, Kalenda seems to be made up in the comic as I don't see a reference to it in the episode.