Inappropriate Nickname

Some people have a nickname, and that's fine. Some canon characters have an inappropriate nickname, usually an embarrassingly fubsy diminutive given to them by their rabid fangirls. That's not so fine.

Would anyone ever call a millenia-old, extremely wise, competent and quite-likely-to-be-deadly-if-you cross-him Elf 'Leggy'? You'd think not. You'd think 'that's just not right'. But people do. 'Leggy' is just one of a whole host of uncanonical nicknames. The angel Aziraphale, messenger of God on Earth, is reduced to 'Azi'. The Jedi Master Qui-Gon Jinn becomes 'Qui'. Severus Snape, feared potions master, is simperingly referred to as 'Sevvy', or 'Sevviekins', or 'Sevviepoo'. And so forth.

Using an inappropriate nickname is a charge. In some cases, they become minis. In the Good Omens Official Fanfiction Summer School, they become mini-Hellpuppies: cute and fubsy and even more rabidly insane versions of mini-Hellhounds. In the Star Wars-verse, they become mini-rancor young.