He had known the very moment they met, of course. At the time Kagami had been terrified of the very prospect, hiding behind his aunt so the scary Senju wouldn 't see him there in the crowd of Uchiha, forgetting for a second that if

he

knew it meant that the other would not. Kagami recognized Tobirama as his soulmate when he was nothing but a terrified child raised on nighttime stories of the demon with red eyes that would gobble him up if he strayed out of bed at night. Tobirama looked passed him like he was just another face in the crowd, unaware of the secret born right under his nose.

Naturally inquisitive and more brave than was good for someone as untrained as him, it didn 't take long before Kagami was seeking out the Senju heir to see if he was really as bad as the bedtime stories had led him to believe. He couldn 't be all

that

terrible if he was living here in the village that Madara-sama had built so they could all stay safe.