From Damu Anna's perspective, why was Mavshibai's joke about getting a kiss so infuriating?

From Damu Anna's point of view, Mavshibai's joke was infuriating because he felt he was being falsely and publicly accused. As Chapter 24 details, Mavshibai's own vigorous service caused her to sway and bring her face close to his. She then turned the situation around, humorously accusing him of 'following' her and trying to get a kiss despite his old age. Anna, a man past fifty, reacted with anger because he felt the accusation was unjust. He retorted, 'Am I such an old man? Am I a fool or completely mad? You yourself put your face to my face and are ready to quarrel with me.' His anger stemmed from being made to look like a foolish old man initiating an inappropriate advance when he was simply performing his service.