[m]I'm looking for new manhwa that is about young women writer (she has a sister that used to see ghosts) and the main character move out to the new flat where she meets a ghost guy ( he is a guardian in that area and protect the buildings and humans against demons. There is also another men who is living in the same flor as the girl and they become friends with time. The ghost can come in to somebodys body . It's similar to ,,pinoccio". Is there anyone that new the title ?

Sounds a little like transparent cohabitation but I’m not sure.
Maybe try this list, https://www.mangaupdates.com/series.html?category=Ghost%2Fs_&filter=some_releases&type=manhwa&perpage=50