Cream Formula for Semi-Permanent Hair Colour. Vegan Friendly & Cruelty Free! Manic Panic, with 40 years of history in leading the colour rebellion, is proud to say their hair colours have always been Vegan and Cruelty Free. And their products are also: Paraben-free, Gluten-free, Ammonia-free, Resorcinol-free, PPD-free, Phthalate-free, & Made in the USA. Siren’s Song is a neon blue-green hair dye that glows under blacklight. For best results, we recommend applying to hair that has been pre-lightened to the lightest level 10 blonde. Style: Classic Semi-Permanent Hair Dye Colour: Siren’s Song Colour Description – Cool Neon Blue Hair Dye Additional Features: Benefits of Conditioning Hair, Resealable Tub For Longer Use, Comes With Instructions Duration: 4 – 6 weeks