- Gaster!Sans may be the first and only one to appear on both AUs.
- In Echotale Echo!frisk and Gaster!sans are a couple
- Gaster!Sans tends to be seductive, and likes to toy with Echo!frisk, doing things the usual sans would do.
- He smokes, but only does it because he thinks it cool
- He's acoholic drinker, drunk mostly of the time
- And there ain't no backstory, so stop whining and complain somewhere else. It's harder than it looks getting information about a barely mentioned character.