Moirail

Coined by American author and webcomic artist Andrew Hussie in his multimedia fiction work Homestuck. Reportedly constructed from the Ancient Greek μοῖρᾰ (moîră, “lot, destiny”). Presented with the coordinate term moirallegience, which seems to be a blend of moira + allegience, with the -ail suffix potentially back-derived from this form. Another potential influence is the term guardrail. In the series, moirallegience is one of four "quadrants" within the complex romance system of the alien troll species, described by Hussie as being similar to the "concept of a soul mate, but in a more platonic sense," for the purpose of pacifying a partner who is dangerous.