Instead of the usual, "dtf" (meaning, "down to fuck"), dts simply means, "down to shnarky" while shnarky means anything from a simple kiss all the way to sexual intercourse and all the kinky things you could imagine inbetween.
Boy to Girl 1: (;
Girl 2 to Girl 1: He used a winky face... I think he's dts.
Dry Thumb Syndrome. An affliction, usually male, where one's "thumbs are dry" caused by lack of sexual activity. Commonly referred after someone has complained from lack of sexual activity.