Instead of a regular April Fools joke, ArenaNet set up an elaborate homage to 8-bit inside Guild Wars 2 called the Super Adventure Box. Beside being an elaborate and nostalgic throwback to Zelda (and fun), it actually has some vore in it, but it's hidden. In the second level, there's a hidden place you can jump down into in which you'll find the Shortcut Worm- an extremely large worm.
He informs you that you can take a shortcut through him, and then opens wide. After jumping in his mouth, you fall down his esophagus and find yourself in the tubular, extremely bouncy stomach of the great worm. The walls are moving, there's green stuff, and you constantly bounce up and down on his bouncy stomach lining. After bouncing your way all the way through, you are unceremoniously extricated off a small cliff- you can even look up and see the end of the worm far overhead.
P.S. This is not the first instance of vore I've found in the game...in another zone, there's an event to guide a human and his donkey to some water. However, as soon as he makes it to the water, a giant lizard pops out and swallows him whole. As you battle the drake you can hear his muffled cries from within the drake, and there's a bar that shows how far away he is from being digested. As you fight the drake vomits out smaller drakes, and if you stand near him he'll swallow you too- no internal views, but your character disappears while he takes some damage inside his belly before being vomited back out.