bestiality

Sexual activity between a human and another animal species.

Less common, but still frequent, are erect penises, more complete female nudes, copulations, and even scenes of bestiality.

Second, the romance option brings up a unique issue: having sex with an alien. It’s somewhat difficult to say what the Christian should think on this issue because, well, the Bible doesn’t talk about aliens. Probably because they don’t exist (sorry to burst your bubble). Would this be considered bestiality? Or is it not bestiality since they are also beings capable of rational and ethical thought and self-reflection unlike usual animals?

Bestial nature, savagery, inhumanity, like (or akin to) an animal's.

the pitiful inadequacy of the reforms and the bestiality of the white society

Any abstract entity similar to a beast.

A status of lower animal.

An animal-like instinct or behaviour.