fake confession of love (a prank among Japanese middle-schoolers)

to tell a lie

lie detector, polygraph

(Internet slang) person who posts a made-up story to SNS as a true story

princess / concubine / woman

scream, shriek

(obsolete) younger princess

title for a daughter of a high-ranking aristocrat or noble

A title of respect used when addressing or referring to a princess or noblewoman.

A title of respect used when addressing or referring to a high-ranking princess or young noblewoman, (like a grand duchess). / A protected young woman who knows little of the world.