Answer:
Frotteurism
Explanation:
Frotteurism is a form of paraphilia whereby an individual derives sexual pleasure from a non-consenting individual by rubbing their genital area against the non-consenting individual, most especially in public, which leads to sexual stimulation.
The man described in the question who rubs his genital area against a woman's thigh in public, without her consenting, can be most likely diagnosed with Frotteurism.
