Missing (2023)

Kyoichi Kurame, a high school student who is called "His Majesty the Demon King" by the people around him, has found a girlfriend. The literature club he is part of is the talk of the town. Ayame Kondo, who was introduced as "Kuume's girlfriend," did indeed have a pretty appearance and a presence that seemed like it would disappear at any moment, and everyone present thought she was "unbalanced" in relation to Kuume.

But...

What is that? What kind of being is "that"? The boy knew. He was convinced.

The Otherworld is always next to this world.