Characters who's alignment changes depending on the run, they tend to be protagonists/player characters, but some exceptions exist. Regardless of what is stated, their alignment is determined by actions and those actions vary depending on the run.
“Caillou is the main character, he was the eighth fallen YouTube Poop character in Mount YTP and...Frisk/YTPtale
“Fuhuhuhuhu is the main protagonist of Usertale (corgimaster). She has brown hair in a style that...Fuhuhuhuhu (Dream tale Sans)