Got to be careful (at least in the US). Many Fortune 500 employers have added both a strip search and a cavity search to the last segment of the hiring process. A tattoo could spell the end to your future career.
This site has become a "cash cow" for the owner's through the sale of advertising in the sidebar. That's all that seems to matter to them. No maintenance, no updates, no moderation.
Why worry? Do you expect the interview will held in the buff? As Kitten said, "It's all about discretion." Don't get a tattoo on the back of your hand or your face and expect to get a job as a Stock Broker or a sales job in Ferrari. Otherwise pursue…
Thinking about it..... and wanting it badly enough to do the work are two different things. Maybe he's just not into the idea as much as he thought or you'd like him to be. Let it go. It'll either happen or it won't.