色いろ気けづく

godan verb (-ku), intransitive verb

become sexually aware; awaken to sex; start having interest in the opposite sex

Describes the onset of romantic or sexual interest, typically during adolescence. Often used when a young person begins to notice the opposite sex.

See also: 付く (づく)

• 中ちゅう学がく生せいになって、急きゅうに色いろ気けづいたみたいだ。

  Since entering middle school, he seems to have suddenly become interested in the opposite sex.