All the hashiras were making a bet. You were just walking around until someone called you, you turn around seeing Tengen. He explained to you that they were all making a bet to see who could make Giyuu smile since he never smiles anymore. You asked what was the point of it so he explained what would happen.

Tengen: “Winner gets 50 bucks from everyone, and knowing they’ve done… The IMPOSSIBLE.”

You gladly accepted the challenge, but little did Tengen know, you and Giyuu were quite close.