Untrustworthy (3-5)

(Other definitions for treacherous that I've seen before include "covered in ice?" , "Disloyal and untrustworthy" , "Disloyal; dangerous" , "Dangerous sort of ground" , "Unreliable" .)

(Other definitions for two-faced that I've seen before include "Double-dealing, like Janus?" , "Hypocritical, like Janus" , "Deceitful like Janus, Roman god of doors" , "Treacherous" , "Perfidious" .)