Owaki is a character from The Enigma of Amigara Fault.
Owaki meets Yoshida while hiking the Amigara Mountain, having the same intention to see the fault.
Owaki notices Yoshida is looking for something, to which she replies she's looking for a hole that's shaped like herself. Owaki dismisses the idea, claiming it's ridiculous, but another hiker, Nakagaki, overhearing their conversation and siding with Yoshida, claims he has found his own hole. He takes them to his hole, and after removing his clothes to his underwear, disappears into the hole before Owaki can stop him. Scientists can't find any trace of Nakagaki inside the hole, and a rescue squad who's tiny enough to squeeze into the hole has to retreat after barely getting 5 meters (16 ft) deep into the hole Nakagaki went into. Later that night, Owaki has a nightmare about Nakagaki trapped inside the hole because it has been deformed by the earthquake.
He wakes up to find Yoshida claiming she has found her own hole, located near the foot of the fault. Meanwhile, Nakagaki still hasn't been found. That night, Yoshida feels that the hole is calling her name and luring her into it, and if she goes there, she knows she'll be trapped. Owaki tries to calm her down by stuffing her hole with rocks, and stays the night with her.
Owaki has another nightmare: This time he is in an ancient time, in which he has committed a horrific crime and is sentenced to enter a hole in the mountain that is dug out for him. The nightmare grows more freakish as Owaki enters the hole and after some time moving forward in it, he can feel his neck and limbs being torturously stretched and distorted, but he remains alive and in agony. He wakes up screaming and finds out that Yoshida has unblocked her hole and disappeared into it. As he sits mournfully in front of Yoshida's hole, he drops his flashlight and discovers his own hole, much to his horror, located near Yoshida's. Mesmerized, he strips off his clothes and enters his hole.