Brothers of y sisters?

Hi. guys may be q sound bit weird but we all encounter many odd situation in our life. suppose you are at some place with your y sister(s). You are aware of the fact that guys are staring at them and scanning every bit of them. What are your personal feelings e.g. being proud of in company with such admirable gals, feeling embared, angery are somehow feeling the same heat that others are feeling but confronting with your lewd thoughts because gal(s) is(are) after all your sister. For open minded guys only