Tachnim was the messenger between his master and Claudie Themond on a deal that no Baelborne could set their foot on Baelborne land. Claudine made the deal to save her baby after she was imprisoned in the tower and left to die there. The deal also kept Claudie's ghost from moving on.
Athel Baelborne just learned that he inherited an estate. Unfortunately, the estate appears to be haunted and is overrun by imps.