I once saw a tattoo where two girls each had half a heart tattooed on their fingers, & when they held hands, it made a whole heart.

What’s that called?

I have a Big Backpiece Tattoo already and was wondering if a Tattoo across my collar bone would hurt bad!?
I already have a whole back piece, koi fish and a phoenix, but im curious to see how a tattoo would feel right under your collar bone across your chest. I was planning to get my kids names.