In fact, the only things in the flat Crowley devoted any personal attention to were the houseplants. They were huge, and green, and glorious, with shiny, healthy, lustrous leaves.

This was because, once a week, Crowley went around the flat with a green plastic plant mister spraying the leaves, and talking to the plants....

Although talking is perhaps the wrong word for what Crowley did.

What he did was put the fear of God into them.

More precisely, the fear of Crowley.

In addition to which, every couple of months Crowley would pick out a plant that was growing too slowly, or succumbing to leaf-wilt, or browning, or just didn't look quite as good as the others, and he would carry it around to all the plants. "Say goodbye to your friend," he'd say to them. "He just couldn't cut it..."

Then he would leave the flat with the offending plant, and return an hour or so later with a large empty flower pot, which he would leave somewhere conspicuously around the flat.

The plants were the most luxurious, verdant, and beautiful in London. Also the most terrified.

Neil Gaiman