No they're quite attached to one another. It's a very common sight to see Horikawa right on Izuminokami's heel, doting on him or chastising him for some chores he failed to complete. Arranging their days around one another. Actually, it's much more common than ever finding them apart. [Did Kanesada need that explicit reminder of his own personal struggles with his partner? Probably not. But it's fun to play these games.]

But they don't quite have the relationship of you and yours.