"Considerate?" joke

As I was on the way home from a long and stressful day at the office, the car phone rang. It was my husband. "Will you be joining me in the whirlpool bath tonight?" he asked. "What a lovely way to spend an evening," I thought. I was about to tell him how considerate he was when he continued, "Because if you're not, I need to start adding more water to the tub."