It's beautifully done, and has raised questions and eyebrows all over the shop - with the internet mostly presuming that they're now dating. Their mutual fans were willing the union to be real that they chose to ignore Franco's caption on Instagram, which credits one "@indiangiver" (after he said "I heart Hermione"). 

@indiangiver is one Cheyenne Randall, an artist who - according to Vanity Fair - "Photoshops elaborately detailed tattoo landscapes over some of history’s most iconic actors: Elizabeth Taylor adorned with a beautiful butterfly on her neck, over a bald eagle’s wide wings. Marilyn Monroe with colored flowers on her kneecaps. Johnny Cash with “Promised Land” fake-inked above his steely brows. Even Princess Diana, rocking a full arm sleeve." 
This isn't the first time Franco's had some "work" done by Randall; he posted this 5 months ago.