It appears to be based on some poem or something like that, but I can't find the original so I'm going to translate it very roughly.
Le Calmant (the Sedative) by Marie Laurencin, translated into Japanese by Daigaku Horiguchi. The Japanese translation provide better (or at least more obvious) context than the English (or the original, for that matter) in this case, though.
Updated
From a bored girl, lots of despair, it's a sad girl.Mukyu...
As expected former pet yukkuri are scum mukyu...Because of that Marisa went to Mister HumanGet it~
The "want to eat udon" that Reimu said was selfish~Awful!
Reibu is now a widowww!Uwaaaaaa!
Barizaaaaa!
Bhyyy!