Learn Dutch: Ze zijn echt permanent, die tatoeages. - They are truly permanent, those tattoos.

In spoken Dutch, speakers often start a thought with a weak pronoun like ze and then add the specific noun phrase (die tatoeages) at the end as an afterthought or to ensure the listener knows what they are talking about. It makes the sentence feel much more conversational and spontaneous than the standard word order.

Could I use a demonstrative pronoun at the start, like: Die zijn echt permanent, die tatoeages?

That would sound a bit clumsy and redundant. In right dislocation, the initial pronoun is almost always an unstressed personal pronoun (like ze, het, or hij/zij) acting as a quick placeholder. The heavier demonstrative word (die) is saved for the clarifying noun phrase at the very end.

Why doesn't permanent get an -e ending, since it describes a plural noun?

Adjectives only get an -e ending when they come directly before the noun they describe (attributive adjectives, like permanente tatoeages). Here, permanent comes after the verb zijn (as a predicate adjective), so it never changes its form, regardless of the noun's gender or number.

Why is the plural of tatoeage formed with an -s instead of -en?