Soulmates!AU where the line on your forearm changes colour according to the other's emotions.
When you do puzzles, have you ever, by mistake, put two pieces together while they weren't meant to fit? They weren't at the right place, but they still sticked together as if it was the right combination. If you lived such a moment, then you have the perfect picture for this story.
You were in the street, living the same life as many highschoolers around your age. You were heading toward a casual supermarket to meet with aquaintances, wearing casual clothes. You always considered yourself as someone absolutely casual, to which nothing really extraordinary would happen; and you were perfectly fine with that. The line on your forearm that indicated the mood of your soulmate changed colours as they were living their own life. It wasn't particularly happy, neither sad. You may meet them someday, you may not, it was the game.
You were abou