Native speaker here.
You could use "æder", as in "En tiger æder min mand.", since "æder" and "spiser" are essentially synonymous. The distinction is that "spiser" is just "eats/eating", while "æder" is a very crude word. It's eating in a greedy or disgusting manner, e.g. unrestrained consuming of large amounts of food.
However, while "æder" isn't exclusively for 'animal-eating', it could definitely be used in this situation as well.
This sentence is memorable but the verb 'æder' - from which we get the english 'eat' - would be the better choice. Danish, like German, has two verbs 'to eat'. Spiser means polite eating. Æder is used mainly with animals, but even then not always - kaninen spiser græs, the rabbit eats grass. With humans 'æder' means to devour, to wolf food down (as it were).