Tybalt: Boy, this shall not excuse the injuries40 That thou hast done me; therefore turn and draw

Romeo: I do protest I never injur'd thee,
But love thee better than thou canst devise,
Till thou shalt know the reason of my love:
And so, good Capulet, which name I tender45
As dearly as my own, be satisfied.
Why is this an example of dramatic irony?