I believe the horror tag is well justified. The series leans more towards a psychological horror rather than something gore based (although there is some disturbing imagery).
The protagonists move between their own world and another world filled with unknown beings (monsters?) that seemingly have the ability to alter perception. Because of this, there is a constant, looming threat of madness and death as the protagonists are hunted by creatures while being unable to trust their own senses, thoughts, and actions.
Hopefully that helps. If you can get through the first two chapters without an issue, likely you will be fine with the rest. However, it is certainly not a series for everyone.
omg thank you so much for replying my question! i will try to read the first episode first
Im quite late but hey I thought this ws a typical isekai manga (which I like) but it turns out this is great lol. I actually like reading it. Its mysterious and does gives me goosebumps sometime but it isnt entirely ghost-like. I really like it :D
waa tysm for answering!! i will catch up with this manga later ^__^
i want to read this because the art looks interesting.. but the tag says horror. is it that scary/disturbing? tysm :}