If you are Asian (aka super dark hair) and bleached your hair, chances are, you will still have a bit of orange undertones left. Purple shampoo cancels out yellow and may still leave you with some brassy stands. Since this is a blue violet hue, I noticed this cancels out brass better than Fanola. However it is drying so follow up with a good conditioner daily and hair mask at least once a week!
It may stain your fingers and nail beds if you don’t wash it off well right after you apply.