Terror Tuesday: Our Hidden Partners

It's time you learned the truth of how things work.
But brace yourself; you're going to find it gross.
You know how you sometimes have "hypnic jerks"?
They're not what you think, man, not even close.
Here, put these on. I know they're kind of dumb,
But what you see through them will blow your mind.
Look at your thigh. Right there, where it feels numb?
Chill out. It's always been there, in some kind
Of symbiosis. There's one on your back,
And in your ear, and halfway up your -- but
That's not the thing. It's laying eggs. Keep track!
The eggs then hatch, way deep inside your gut
And burst out when you're sleeping. No, there ain't
A thing that we can -- oh, another faint.