Does massage for the purpose of slimming, performed by one woman on another woman in specific areas of the body such as the buttocks, legs, and abdomen, break the fast of the fasting person?

Based on Fatwa No. 39283, a woman must adhere to the Shariah guidelines when massaging others. As for fasting, massage does not affect its validity, as it is not among the things that invalidate fasting mentioned in Fatwa No. 33598.