Oh, that one was in my to-read list (now it's my about-to-read list). The ratings are stellar and I'm definitely interested in it. Thanks for the suggestion!
Here's another series about a guy who winds up in a relationship with a ghost: https://mangadex.org/title/455/my-lovely-ghost-kana. It's been a long time since I read it, but I remember it as being funny and a bit fluffy. Stuff like the ghost chilling beer cans in her cleavage and using a "dead" cellphone.