• 1. When a villager picks up a catchphrase you don't like. e.g. You made your Apple say "I'm kawaii", but somehow your Barold picks that up too. You can report Barold as "problematic on account of bad catchphrase" and Isabelle will wash his mouth with soap and make him say something else.
• 2. When a villager wears a PATTERN you don't like. e.g. A naughty friend went to your Able Sisters and put up a sexually explicit pattern without you knowing, and your Midge wears it around. You can report her to Isabelle as "guilty of wearing bad clothes" and she'll make her wear a barrel for a day to respect dress code.
• 3. When a villager has a letter you don't like. e.g. A naughty friend mailed your Anicotti a "You are fugly" hate letter and she starts showing it to you. You can ask Isabelle to get rid of that mail and she will do so by holding a knife against Anicotti's neck.