Green’s Dictionary of Slang

kinkless adj.

[SE kink]

having straight(ened) hair.

[US]O.O. McIntyre New York Day by Day 11 Sept. [synd. col.] There is another specialist in the black belt who has an engaging sign. It reads: ‘Do you crave to be kinkless? See me. My motto is “Straight as an arrow.”’.