I always wondered, who tied up Reed? Was it the monster?

what happens off-panel is none of our business.

I say Ben because he'd be mad about being a monster and do things like compress Reed into a flask or yank him out of shape.

With his big King Charles fingers? Perhaps he's more delicate and nimble than he appears at first glance...

Also, why does it take Sue so long to turn invisible and, if she were invisible, would that make any difference given the monster already had her in his hand? Thanks, I'll take your answer off the air.

Presumably the Mole Man did it somehow? It's notable that nothing like that occurs in the actual story.

THIS HAS NEVER BEEN REVEALED. I think he did it to himself