sex activity vs immoral

sex activity is a noun but immoral is not a noun.

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

sex activity (noun)	immoral (noun)
activities associated with sexual intercourse

sex activity (adjective)	immoral (adjective)
	deliberately violating accepted principles of right and wrong
	not adhering to ethical or moral principles