Occupied? The nerve— in the bathroom, while his bladder is about to explode? Shōyō inhales, can feel an annoyed smile pulling his lips up simply so he doesn’t frown like a madman. In Paul’s residence? He is not going to pee on the door, on a plant or outside.

Maybe if he just keeps knocking (which he does, louder, continuous and more obnoxious)—

“Come onnnn, I have to pee. That’s what the bathroom is for.”