Many a Little Makes a Lot

"Black Dick, it can't go out?"

"No, it can't."

At the lodging entrance, we tried several times to take the harpy outside, but it couldn't leave.

Whine. Whine.

It couldn't open the door, and even when it hit it with all its might, it didn't leave so much as a scratch. I even opened the door for it, but it couldn't approach the bluish portal beyond it.

It couldn't even reach it with its fingertips, as if an invisible wall were blocking its way.

'So once it comes in, it can't leave my lodging, no matter how much it wants to.'

Meaning it had to pass through the envelope to come or go.

Well, that was fine, then.

To be honest, I'd been worried about it for a while. Sooner or later, there'd be a time when we had to leave, and I was afraid the harpy might slip out of the lodging while we were gone...