angel next door isn't over at all, in fact its still continuing, with vol 11 releasing in march 15th, Season 1 ended in vol 4 with a bad adaptation, however the manga is doing very well even if its behind the anime.
I don't k ow if you are aware of this romance series but "The Nagel Next Foor Spoils Me Rotten" is one of those series that starts before they meet and becomes a relationship, very diabeticaly sweet and continues further on.