choosing one of three options

(horse racing) betting on the first 3 winning horses, in order

to appeal to the court, police or other public place, and compete which one is correct publicly; to bring a lawsuit

(genetics) mutation

an adult son residing with his parents; generally has not yet or can not come into family inheritance / a female servant working in a daimyō, ōoku, or other high-ranking house

room rent

at-home clothes

(Internet slang) dirty room

everything

(colloquial) current boyfriend