House is at a three-way intersection with one street thrusted at it, so some feng shui clown, no doubt, told its owner he needed a large mirror to deflect and chase away evil spirits. To make sure demons coming from any angle have no chance, it's a convex mirror!

I know how these charlatans think. "Sir, your second floor toilet is directly over your first floor study, with the shitter right over your desk. That's why all your thoughts are shit. You must destroy your expensive toilet immediately!"