The full story has never really been explained to Sougo, though he has gleaned bits and pieces in his short time of knowing Seiichi. He knows that Seiichi's rebirth as a shinigami is relatively new, and he knows that people can reborn as reapers at all now. He knows that Seiichi had a life before death cruelly stole him away from it, and that he remembers that life.

He only knows a little bit of what happened in that life, however, and it's only through friendly pestering that he's ever able to drag the tiniest bits of information out of Seiichi about the sorer subjects of his life. Sougo's gormlessness is sometimes disarming enough to allow him into people's lives, but it's still not enough to get the god of death to completely share all of his secrets with him.

But he's gotten enough out of him still. A location of Seiichi's death, and a date of when it happened as well. That Seiichi would possibly visit the location of his own death on that important day also occurs to Sougo, but that someone else from Seiichi's previous life might show up as well doesn't.

He can't see the shinigami right now, but as he cautiously approaches the spot, he can at least see the middle aged woman who is standing there as well, laying down flowers for someone she knew before Sougo was even born.

Before Seiichi can have his confrontation with his wife, Sougo unwittingly steps forward, accidentally blocking Seiichi's path to Kana as he looks down at the flowers with a solemn expression, drawing some attention from the woman who set them down, even if she doesn't speak to the young man.