http://en.wikiquote.org/wiki/Richard_Stallman#On_sex
"On sex
[P]rostitution, adultery, necrophilia, bestiality, possession of child pornography, and even incest and pedophilia ... should be legal as long as no one is coerced. They are illegal only because of prejudice and narrowmindedness.
Some rules might be called for when these acts directly affect other people's interests. For incest, contraception could be mandatory to avoid risk of inbreeding. For prostitution, a license should be required to ensure prostitutes get regular medical check-ups, and they should have training and support in insisting on use of condoms. This will be an advance in public health, compared with the situation today.
For necrophilia, it might be necessary to ask the next of kin for permission if the decedent's will did not authorize it. Necrophilia would be my second choice for what should be done with my corpse, the first being scientific or medical use. Once my dead body is no longer of any use to me, it may as well be of some use to someone. Besides, I often enjoy rhinophytonecrophilia (nasal sex with dead plants).
http://stallman.org/archives/2003-may-aug.html
I am skeptical of the claim that voluntarily pedophilia harms children. The arguments that it causes harm seem to be based on cases which aren't voluntary, which are then stretched by parents who are horrified by the idea that their little baby is maturing.
Link
There is little evidence to justify the widespread assumption that willing participation in pedophilia hurts children.
Granted, children may not dare say no to an older relative, or may not realize they could say no; in that case, even if they do not overtly object, the relationship may still feel imposed to them. That's not willing participation, it's imposed participation, a different issue.
Link
I've read that male dolphins try to have sex with humans, and female apes solicit sex from humans. What is wrong with giving them what they want, if that's what turns you on, or even just to gratify them?
http://stallman.org/articles/extreme.html"