Dance over!
CATECHISM OF THE CATHOLIC CHURCH
2358 The number of men and women who have deep-seated homosexual tendencies is not negligible. This inclination, which is objectively disordered, constitutes for most of them a trial. They must be accepted with respect, compassion, and sensitivity. Every sign of unjust discrimination in their regard should be avoided. These persons are called to fulfill God's will in their lives and, if they are Christians, to unite to the sacrifice of the Lord's Cross the difficulties they may encounter from their condition.
2396 Among the sins gravely contrary to chastity are masturbation, fornication, pornography, and homosexual practices.
2357 Homosexuality refers to relations between men or between women who experience an exclusive or predominant sexual attraction toward persons of the same sex. It has taken a great variety of forms through the centuries and in different cultures. Its psychological genesis remains largely unexplained. Basing itself on Sacred Scripture, which presents homosexual acts as acts of grave depravity, tradition has always declared that "homosexual acts are intrinsically disordered." They are contrary to the natural law. They close the sexual act to the gift of life. They do not proceed from a genuine affective and sexual complementarity. Under no circumstances can they be approved.
Where is homosexuality defined as a sin?
What is your confusion?
From the Douay Catholic Catechism of 1649
CHAPTER XX - The sins that cry to Heaven for vengeance
Q. 925. HOW many such sins are there?
A. Four.
Q. 928. What is the second?
A. The sin of Sodom, or carnal sin against nature, which is a voluntary shedding of the seed of nature, out of the due use of marriage, or lust with a different sex.