Manic Panic on virgin medium brown hair

Semi permanent dyes like Manic Panic really do not stick well to unprocessed hair. You may find it washes out in the first wash or you may get staining that never completely goes away so it's best to do a strand test. Rockabilly blue is one of MP's stronger colors and is hard to get out of bleached hair and notorious for making a mess of due to rub off. On unprocessed hair that it will have trouble sticking to I think it might be really awful with rub off.

Blues often do not look blue unless applied to a very pale base like the color inside a banana peel. It will probably look muddy, but again a strand test is necessary.

Blues just don't look nice on a brown base. Even if it looks blue to begin with it will fade to a browny blue, strange muddy swamp colour

Yeah, I'm sorry, just not going to happen 🙁

Any colour that's going to show at all on a mid brown base is going to look black with a hint of colour in the sun. It'll only work with pink, purple or red though. Other colour won't do anything or will look horrible. And as said, won't last long at all.

I used to do this when i went to boarding school and wasn't allowed to dye my hair. Unfortunately on virgin hair, these dyes only last a few washes. 4-5 if you are lucky. Blue was the worst color to stick. And it always came out black with undertones in the sun