Can someone from the sciencey side of tumblr please explain this ?
This is called shape memory. It’s made from an alloy of titanium and nickel (I believe it’s called nitinol). It has the ability to “remember” the shape it’s taken.
When cold you can bend it whatever which way, but once you heat it (or in this case put it in what I presume is hot water) it will take the original shape.