It’s a story of some guy with a ghost/spirit in his room. The ghost/spirit is another guy, and at the end of the story the ghost disappears and it’s super sad or something idk (I honestly don’t remember)
U didn't mention whether it's a bl or not but if it is then it might be https://www.mangago.zone/read-manga/lonely_to_organdy/
Not really sure but is it https://www.mangago.zone/read-manga/one_room_angel/ ?
The jealousy thing in these stories are starting to get annoying, it’s so painfully obvious that that’s his brother or something and he’s still jealous