Date & Time: 07/10/2018 13:54
Frequency: Constantly
World name: Odin
Character name: Truffell Lanverlais
Retainer name: None
NPC name: None
Monster name: None
Class/Level: All classes
Party or solo: solo
In-game time: None
Area and coordinates: None
Housing: None
Steps:
1. Create a character in either of the available worlds.
2. Attempt to give the character a name containing the phrase "fella", e.g. Truffel Lanverlais, Fella Lanverlais
3. Get an error screen saying "That character name cannot be used. Please input another.".

Conducting a search on Lodestone's character search reveals that no character with a name containing the phrase "fella" exists, suggesting that the phrase is unnecessarily forbidden from use.