The Boisvert Mansion is the Val Royeaux residence of Comte Boisvert.
It is only accessible during the quest Of Somewhat Fallen Fortune
Comte Boisvert invites Josephine Montilyet to meet at his mansion so he can give them information on the 'House of Repose' assassins targeting Josephine. In an ironic twist of fate, he turns out to have been imprisoned and replaced by a member of the House, stuffed in a closet that apparently has great value to him (to the point where he tolerates being bound and gagged for long enough to find a locksmith rather than risk damaging the doors).
- The map only refers to this area as Val Royeaux