Monkey? That looks like a woman with a cow’s tail.
That would be a huldra.
Norwegian forest elf, usually a very pretty lady, except for the tail . . .
A tactful young man was dancing with a (disguised) huldra at a party one time and noticed that her tail was showing. He whispered quietly to her, "Your garter has come untied, lady." She was grateful for his discretion and gave him good luck all his days.