Blac Chyna's Sharpie Talk Is BS ... Future Ink Is Permanent (PHOTO)

Blac Chyna is trying to convince the world her Future tattoo isn't the real deal -- that it's just a Sharpie drawing -- but we have the proof it's 100% authentic.

Chyna and her friends posted a video on Snapchat Wednesday night where they all had "Blac Chyna" written on their hands in Sharpie, and then she asked followers to do the same in solidarity.

But she ain't fooling us. TMZ has obtained a set of photos that show Future's tattoo artist, Steve Wiebe, inking the couple together several weeks ago ... just as we first reported.

We're told Chyna is pretending the tattoo never existed because she's hurt after Future publicly humiliated her by tweeting his single status. Chyna was under the impression they'd been dating exclusively for over a month.