A bloke shortly getting married decides, as a special honeymoon night gift, to have his wife-to-be's name 'Wendy' tattooed on his willy.
He goes to the tattooist, who explains that he's willing to do it but the wife will only be able to read her whole name when the member is in its tumescent state - normally, just the w and y will be visible On this understanding, the bloke gets it done.
They are married and after, go on their honeymoon to North Wales. Out one day, the bloke gets caught short and pays a visit to the public loos, where he relieves himself. As he's doing this, he glances across and down and sees that the fellow next to him also has a W-Y tattoo. So he asks, "Ah, your wife's name is Wendy too?'
"No." Comes the reply. "I'm a tour guide round here: it says 'Welcome to Llanfairpwllgwyngyllgogerychwyrndrobwllllantysiliogogogoch, have a nice day'."