What is wrong with straight sex why introduce electricity create your own sparks with jolly good f*cking.
I don't know about using car battery, but saw in a bdsm movie one time where the used a 6 volt car battery charger (called trickle charger) and clamped leads to her nipples and later to his balls. Wow wow wow.
Your **** would rather have mains electric power 240 volts and your balls will light up.
I would agree a car batter is just too strong and dangerous. For those that have not tried electrostimulation on themselves or others it is just another variation of sex and pleasure. Personally I have found electrostimulation of my **** and balls to be a whole different level of pleasure and satisfaction. I will try a variation where my **** is the ob
If you really want to get into shock, at least do it safely. Using a car battery is NOT safe. The amperage is too high.
If you want to flirt with electricity, get yourself a TENS unit and try that on your **** and nipples.
If you want to get a real charge, then get an Electro-Muscular Stimulation (EMS) unit and use that. You can more than sufficiently shock someone with an EMS to achieve your desired ends unless you wish to do real damage or kill someone.