Priest Seto had decided to be considerate and buried Atem with honor by burying mummified cats with him. Instead of just having the ghost of the Pharaoh in the puzzle, Yugi is also haunted by three cats. Based on the post from the yugioh-thoughts tumblr.

Kaiba Seto is beset by custom-made Blue Eyes White Dragon plush toys. He's determined to get to the bottom of this mystery, although it's not much of a mystery. At all. Jounouchi/Seto.