My Indents In Your Skin

"When did you write that on your hand?"
"I didn't."
These markings just suddenly appear from nothing. It started when she was young, all up through her teen years. She's the only one who thinks its normal now.
He reads the markings that come onto his skin. The letters, words numbers, everything you can think of.
But he didn't write it.
He doesn't know who did.