The electricity that courses through your body whenever you're together. The way you fit perfectly in her arms, powering you up. The voltage you feel as the relationship sours, when you stick your ring into a wall-socket. [Artifacts via DesignMilk]
Dry human skin has a resistance of between around 200KΩ and 12MΩ, depending on humidity, hydration levels, electrolyte levels, skin type, etc. This will become important in a minute.
Most people, when sticking forks, knives, etc. into sockets, are only sticking something into the positive lead; there is no intrinsic path to ground, so they themselves become the ground path. Since babies and small children tend to have a lower total resistance than adults, they get more current through them, which is why they die more.
This ring, however, has an intrinsic path to ground, and one that presents a resistance of only ~1Ω. Therefore, as electricity follows the path of least resistance to a ground, very, very little of the electricity will flow through your body. Electricity will follow all paths though, with respect to resistance; given a choice between a 1Ω path and a 1MΩ path, .0001% of the electricity (one millionth) will go down the 1 million ohm path.
So, given a 1MΩ skin resistance, 120v and 15A (max) of current, upon plugging the ring into the socket your body will receive about .00012A, or .12mA (your USB connection delivers 500mA, albeit at 5vDC, for comparison). This is not a stunning amount of electricity.
Of course, this will all happen for about a tenth of a second, before your circuit breaker trips off. The ring might get somewhat hot.
tl;dr plug away into a socket of your choice; just be prepared to flip circuit breakers back up.