Mina often got doodles on herself. Whether it be from herself or her friends, there was one common thing that kept recurring: Some more doodles responded, that weren't from anyone she knew of, so far.
It happened all the time, with a lot of people. Some lucky people got soulmates, which used to just be some little story parents told their kids to help them go to sleep with happy dreams at night. Over time, however, something odd happened, which many scientists have no clue what happened. One person would draw on their arm or something, and it would mysteriously ink itself onto another person's body, in the exact same spot. These people started getting together, and the world collectively agreed: These people were soulmates. Whether it be some haywire Quirk that went a bit haywire, or it was just God getting Cupid to be a hell of a lot more chaotic and creative with his tactics, no one knew.
Mina was sitting happily in her dorm, chatting chipperly to Tsu, Kyoka, and Ochako, collectively (Minus Tsu, really) teasing the poor pink-cheeked girl about her obvious crush on Midoriya. It had really just become a common habit to have a marker or a Sharpie of some sort on her purple table, letting people draw on her arms to talk to the mysterious person who received her personal collages of art.
"What's Midoriya up to today, mnn?" Mina hummed, grinning playfully, watching Ochaco's reaction curiously. Mina'd grabbed a marker and was drawing on her knee without really looking. Scribbles, really. Kyoka had her left forearm, Tsu had Mina's left palm, and Ochaco wasn't drawing. She was just there to talk.