deceive
譎 centers on deception through words: to deceive, mislead, or speak falsely.
譎 combines 言 (speech) with 矞, which likely contributes the sound and may relate to piercing or twisting, suggesting deceptive or twisted speech.
Words (言) twisted like a thorny branch (矞) deceive the listener.
For ケツ, imagine a con artist deceiving someone with a fake contract, then suddenly getting caught and yelling 'Kets!' as they flee.