The members of House Guillane aren't so much a noble house as they are a very prominent artisan family. Originally starting out as tailors and weavers that branched out into leatherwork and armor-making, they worked their way through the ranks of Ishgardian society through a combination of good business sense and a reputation for honest work. Outside of their work, they're also well known for being a neutral party amongst the ever chaotic political and religious happenings of Ishgard.
Their most notable attribute, however, is the sheer size of their family. The Guillane brood is known for being quite large, with observers quickly losing count of all the siblings and cousins and grandchildren. How do they all remember each other's names?
Not only is the family big, but it's also fairly recognizable in public: it seems that red hair runs particularly strong in this family line, with roughly half its members sporting locks of bright red and orange.