Board Thread:Lore Discussion/@comment-72.77.73.35-20140408131341/@comment-26381646-20150508221611

I believe that if the dragonborn had made a deal with Hircine and several days, months, years whatever the case may be later decided to make a deal with Nocturnal, at that point Hircine would intervene and prevent some sort of "betrayal". As powerful and knowing as the series lets you believe the Daedra are I can't see one of them allowing another to "take" something that is theirs through whatever deal was made previously. This would go for all the Daedra not just these two individuals. Anyway that's my thoughts.