Snitcher and Two-timer

Snitcher noun - A person who provides information about another's wrongdoing.

Two-timer and snitcher are semantically related In some cases you can use "Two-timer" instead a noun "Snitcher".

Two-timer noun - Someone who deceives a lover or spouse by carrying on a sexual relationship with somebody else.

Snitcher and two-timer are semantically related in person who is disloyal topic. Sometimes you can use "Snitcher" instead a noun phrase "Two-timer".