The smell from the entrance to the Gekko's Labyrinth is, to say the least, agonizing to the point of making your head burn and you want to vomit. On the floor there are several indistinguishable footprints, bony carcasses of various creatures, and part of the floor was stained with dried blood. The scene is chilling.
As the group led by the young Kalen gazes upon it, they are in shock. Most of them are used to seeing blood, because they have killed dozens of monsters before and after entering the Heavenly Abode for the first time, but even a high level of tolerance for this kind of thing was not enough to make them not bother with the entrance to this cave.
Kaito's a little bothered too, but after literally ripping chunks out of an Asmoth Crocodile with his own mouth, he's gained more tolerance for disgusting things than most Duelists.