pleasure vs sex activity

pleasure and sex activity both are nouns.

Word	Noun	Adjective	Verb	Adverb
pleasure	Yes	No	No	No
sex activity	Yes	No	No	No

As nouns, sex activity is a hypernym of pleasure; that is, sex activity is a word with a broader meaning than pleasure:

Other hypernyms of pleasure include sex, sexual activity, sexual practice.

pleasure (noun)	sex activity (noun)
sexual gratification	activities associated with sexual intercourse
an activity that affords enjoyment
something or someone that provides a source of happiness
a formal expression
a fundamental feeling that is hard to define but that people desire to experience