Sienna Spiro for PETA U.K. (Courtesy PETA U.K. )Sienna Spiro wants animals to be more than just Visitors in your home. She’s teamed up with PETA UK for a campaign urging people to adopt animals from shelters rather than buying them. There’s thousands and thousands of amazing animals that really need homes.” But when she’s “off duty,” she tells Variety, she doesn’t walk around with a bouffant and boots — and nobody recognizes her. “Sometimes having hair that’s different from my everyday hair, or when I put my boots on, allows me to kind of step into something and have a level of confidence and separation from the way I felt writing [my] songs.