Again i would ask for your definition of natural for you to call it a corruption of the same or unnatural.
From your statement, Your objection Only seems to be with anal sex between two men. Because homosexuality in totality includes everything a heterosexual relationship has with the exception of how the act of physical sex.
Just because I provided one example doesn't mean it's all there is.
A natural relationship is between a man and a woman, where they have the right sexual reproductive plumbing to raise a family and propagate a society.
Societies don't grow on vibes, feelings and what sexual deviances are the latest trend, they grow with the strong foundation of a the stability a heterosexual relationship puts in place.
A society of homosexuals will die out as they cannot propagate without intervention or adoption. Maybe that's what we need to do to get rid of this nonsense.
Even then, anal sex is a risk factor of anal and colorectal cancer for doing things it wasn't designed to do. Why place a burden on an already incompetent health system just to satisfy deviant urges?