Green eye, blue eye

Walking along a familiar riverbank this morning, I noticed a cat licking some grass. It had been raining during the night and although it had stopped some hours previously, the dew still clung to the grass, offering the thirsty cat some fresh beverage refreshment. As I approached, it looked up at me, as if it knew me, as if saying, "Alright there, Tom. This rain water is delicious. You should try some." I then noticed something unusual. His left eye was emerald green and his right eye ocean blue. He blinked at me twice, then bent down to continue enjoying his morning brew.