"Human" is a construction (construction: a fake structure), a word that defies definition. Certainty of identity requires certainty in humanity. If you can't be sure you are human, what about everything else? Are myths reality, reality a myth?
The unicorn is mythical, strange, mysterious. When it appears in reality it is always artificial. Dream of unicorns, find them on your doorstep...
Does the unicorn disturb you?
Or are you secure?