Ode to the Gecko

The first night I stepped in the shower and saw a small gecko/lizard-type thing, I wasn't scared or concerned, but did expect Josh to at least catch it and release it outside when I told him about it. Instead, he just shrugged his shoulders and said, "so?" The next night when it was still there, Josh pointed out that the spiders that had been living in the corners were gone--probably courtesy of the gecko, so I decided he (she?) could stay. It's been at least two weeks now. The gecko lives in the drain and when you turn the shower on, he pokes his head out of the drain, then runs to the corner to hang out until you turn the water off again. I believe he has turned into a pet, because I noticed his tail has been pulled off recently and I find I'm actually concerned and wondering what happened...