Does the “box frame” change width during manipulation? I assume you mean to check if it’s X is >= Defender.X and it’s Y >= Defender.Y?
if box.AbsoluteSize.X >= Defender.AbsoluteSize.X and box.AbsoluteSize.Y >= Defender.AbsoluteSize.Y then
--It is covering the whole Defender
else
-- it isn't covering the whole Defender