No u have to be 18 no matter what and with an adult.
I don't know about policy for the age of 15, but when my daughter was 17, I was able to sign a consent form to allow her to get a tattoo at Skin Factory. I had to be present, sign a consent form, and sign next to her initials on the regular waiver. Parent and child names have to match as well (or you must have proper legal paperwork explaining the difference).
I'm pretty sure legally you can with signed parental consent, but I don't know if the artists there would be comfortable. A lot of that seems like it's up to the artist's discretion.
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