I love how your mental image is Arthur kissing Merlin out of sheer frustration more than anything else. Which seems pretty in character to me, actually. Your bit of knowledge seems intriguing though. Would the locals (shorter and easier to type) warn Merlin about what can happen? Maybe advise him to have somebody on Earth to keep hold of him? Or would Merlin, acting as he always does, just go blundering in and manages to reach out to Arthur for help (or hears/senses Arthur trying to get hold of him)? ...Right, I guess this is getting written at SOME point then...

Are we talking about a whole other fic for the Kama Sutra? Because that's just being demanding. Although I am tempted to try one just to see how little sex I can mention, just in revenge. ;P You seem to have put a lot more thought into it though...

And why does it have to only be a one-way thing? If I'm suffering, I'm taking you down too!