Daniel "Oz" Osborne (played by Seth Green) was a musician and werewolf. He was Willow's first boyfriend. For three nights each month, Oz would change shape. If he was not put into a cage or locked up, he would roam Sunnydale from the time the sun set until it came up again in the morning. Being a werewolf gave him increased strength, endurance and healing. As a werewolf, his mind was similar to an animal and not a human.