What are your favorite small recurring motifs in fics?

Of course every fic has a main story and a few side ones, but I'm interested to know what are your small recurring motifs that doesn't necessarily have any serious meaning or impact the story.

For example, in Remain Nameless, Draco keeps making up new nicknames for Harry based on "The Boy Who Lived". Such as "The Boy Who Lived to Cock Block" and "The Boy Who Doesn't Know How to Die nor Comb His Hair".

Another example - Draco's nicknames for Ginny as her ranking in his "Weasleys Most In Need of Dying In a Fire" list changes in BLOODY, SLUTTY, AND PATHETIC.

Don't get me wrong, it doesn't have to be just nicknames lol. Another example is Theo's Queen songs choices throughout Secrets and Masks.

Looking forward for your answers ♥️ and sorry for my grammar, English is not my native language.