From snookums to honeybun, English has a robust supply of super-cute nicknames for sweethearts, lovers, and significant others.
In linguistic and rhetorical terms, many words and names like this fall under the heading of hypocorisms. Derived from a Greek word literally meaning to caress, hypocorisms can be either jokey, short-form pet names (think diminutives like Johnny from John, or Patty from Patricia), babyish terms and nicknames (like daddy, momma, or meemaw), or simple terms of endearment (like honeybun).
There’s often no rhyme or reason as to what makes a word a good term of endearment in a language. Many of them depend on who is being addressed (words for kids differ from those for lovers, for instance), and they tend to fall in and out of popularity over time (you probably have not heard of someone being called a “powsowdie” since the early 1600s). But one that’s definitely in vogue at the moment is pookie.
POOKIE IN GERMANY

Having spiked in popularity on social media in the early 2020s, pookie or pookie-bear has seen something of a resurgence in recent years, albeit sometimes somewhat ironically, in an overly twee or cutesy context. The word itself, however, is thought to be far older—although its origins are still somewhat misty.
One popular online theory claims that pookie was adopted into American English from German sometime around the turn of the last century. That theory holds that it was originally not a romantic term for a sweetheart or lover, but rather a tender name for a young child.
It’s certainly not unheard of for words used of children to become adult romantic terms (think baby, babe, and even poppet). If we follow this theory, it’s possible that the German term of endearment Püppchen (which literally means 'little doll') eventually evolved into pookie in English. As neat as this explanation is, though, there’s scant evidence to back it up; in fact, there’s scant written evidence of the word pookie at all as a term of endearment before the late 1900s (when its use was further popularized by the name of Garfield the Cat’s teddy bear).
POOKIE IN SCOTLAND & IRELAND

So if this theory isn’t accurate, then which one is? Well, alternatively, the origins of pookie might not lie in Germany, but rather in the Celtic cultures of Scotland and Ireland.
An even earlier record of the word “pookie” in English dates back to the mid-1800s, in a short story written by the Scottish author George MacDonald, “The Fairy Cobbler,” published in 1867. His use of the word is not as a term of endearment, though, but as the name of some legendary creature—presumably a local variation of the legendary púca, a kind of impish, shapeshifting, troublemaking creature in Celtic mythology and folklore.
From there, it’s possible to imagine how the name of the pookie (or the phuca, pookie, or pooky, as it is also known) might have come to be playfully used by parents as a nickname for a similarly impish or mischievous child. And from there, the word could similarly have come to be used as a jokey name for a sweetheart.
THE FINAL WORD

As neat as this theory is, however, there’s likewise little written evidence to back it up. So, until more written evidence of pookie as a term of endearment is found, it’s unlikely we’ll be able to say for sure which of these theories (if any) is correct.
