It's blissful...then annoying. You melt into your loved one's shoulder and put one arm across them. You're both relaxed, listening to each other's breathing. Your hearts seem to be beating at the same time, and you feel like you could stay there forever.

Then it starts. First, there's just a tiny tingle in your fingers. Then the numbness and prickling creep up your arm. Your shoulder gets stiff and if you don't move, the condition becomes painful. The moment is ruined and you're forced apart.

Until now. One couple got tired of the struggle and invented a pillow shaped like a tiny foam tunnel. One person can slide their arm through the arch to elevate the cuddler's head. Their tagline says it all, "It keeps your arm from falling asleep."

Why Your Arm Goes to Sleep

That feeling is actually called paraesthesia. When you're laying on that arm and shoulder, the rest of your body weight puts pressure on blood vessels. The nerves in that part of your body don't get enough blood, so they become deprived of nutrients and fresh oxygen and start to basically panic.

Nerves are like electrical wires throughout your system. When they work right, sensory input travels seamlessly along the proper channels, in this case, form your arm to your brain. When the nerves don't receive enough blood, they start to short out. Some of those signals can't travel right.

The nerves start to discharge, sending alarm impulses to the brain. The brain can't interpret the signals the usual way, so it translates those signals as pain, numbness, prickling and heat all at once. When you move and the blood rushes back in, those nerves receive a jolt of fresh stimulus, so for a minute the sensations get worse.

Stop Paraesthesia

The pillow is called Coodle, and it will cost $65 on Amazon. Most of us will have to wait, though, for comfortable cuddling, because it's currently sold out.

Coodle's inventor says it also helps side sleepers because it provides the correct positioning for the head.