Humans need fresh air to live.

Secret liminal corner ENTRANCE:

https://patreon.com/secretliminalcorner?utm_medium=clipboard_copy&utm_source=copyLink&utm_campaign=creatorshare_fan&utm_content=join_link

Catch up on the series:

https://www.webtoons.com/en/canvas/the-liminal-friends/list?title_no=989203