bestiality vs sexual activity

bestiality and sexual activity both are nouns.

Word	Noun	Adjective	Verb	Adverb
bestiality	Yes	No	No	No
sexual activity	Yes	No	No	No

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

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

bestiality (noun)	sexual activity (noun)
sexual activity between a person and an animal	activities associated with sexual intercourse
the stupid brutal quality of a beast