Really, you should be able to outrun the goo, seeing as it doesn't have legs, yet you somehow don't. It latches onto you almost greedily, coiling up your legs and causing you to trip onto the concrete.
Your hands are stuck in a pile of the stuff, the slime completely enveloping you before starting to melt into your skin. An itch starts across your mouth, yet you can't open it within the goo. It feels like an eternity until you can get any semblance of freedom, newly sprouted wings flapping.
A beak opens as you pant, your beak, newly formed just like talons folded beneath legs not quite done changing. You should be feeling terrified or afraid, yet you can't bring forth any emotion save for idle curiosity towards your newly feathered body.