There is a Bugbear occupying a ten foot square, (lets say four 5 foot squares).
Another Bugbear wants to enter the area, but the Rules Lawyer says it can't because the first Bugbear occupies the original ten foot square.
I get that a Bugbear is large, (7 feet tall). But I don't get that it should be 10 feet wide (or even larger than 5 feet wide), thus preventing the second Bugbear from entering the same ten foot square.
Does anyone know that rule?