Actually, ROD the OAV is very loosely based on the original manga ROD. ROD the TV series is based on the sequel to the original manga.
ROD the TV series has Yomiko in it later on (whoops, spoiler) and Nenene was her best friend (who seems to have an interesting crush on Yomiko). Nenene is looking for Yomiko, who seems to have disappeared, and she is joined with the three Paper Sisters Detective Agency, who have paper powers as well (though not nearly as powerful).
The action is very nice in some episodes, but mostly it's about a bonding between the three sisters and Nenene. It gets very sappy at times, with those "awww, how cute" moments.