Hello ~
It is and you don’t necessarily have to use bleach. If you’re patient, just washing your hair as you usually do will fade out the colour, which should be really fast since blue/grey disappears really easily. If not, just substituting body wash for shampoo will strip the colour (you can do the same with dandruff removing/fortifying shampoos) and lather it in until your hair turns blonde, but I really wouldn’t suggest doing this too often.
Pretty much, once it fades out completely, you can just put in the pink.
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