Lissome [lis-uh m] – Adjective
1. Bending or moving gracefully or with ease and lightness; lithe, supple, limber, agile, etc.
2. Lithesome or lithe, especially of body; supple; flexible.
"Daniel Browning Smith boasts the title of "the most flexible man alive" and regularly pushes the limits of his lissome body."
Surreptitious [sur-uh p-tish-uh s] – Adjective
1. Obtained, done, made, etc., by stealth;
2. Secret or unauthorized;
"He watched her surreptitiously as she waited at the bus stop."
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