Much like beastiality, homosexuality is disgustingly unnatural.
'Disgusting' is a purely subjective term, refering to personal taste, so I won't argue with that. I find religious disgusting - to each his own, eh?
But why would you say 'unnatural'? What do you mean by that? What're your arguments? Just your socialized disgust reaction? In fact it isn't unnatural, and even if it were, why is that a criticism? Is your argument that sperm should only go into a vagina for producing offspring? In that case is homosexuality any more unnatural than masturbation? What're your views on masturbation and wives giving husbands BJs?