The phrase "fucking hot sister" might be used in certain contexts to express admiration or attraction towards a sibling. However, this type of language could be seen as expressing incestuous desires which are often taboo. Siblings are family and their relationships are based on love.
However, it's essential to consider the potential impact of using such language, particularly in public or online spaces. The phrase may be perceived as shocking, off-putting, or even hurtful to some individuals, especially if they have experienced trauma or discomfort related to family dynamics. fucking hot sister