stealth

The attribute or characteristic of acting in secrecy, or in such a way that the actions are unnoticed or difficult to detect by others.

An act of secrecy, especially one involving thievery.

To conceal or infiltrate through the use of stealth.

To have sexual intercourse without a condom through deception (for example, removing the condom mid-act).

Of a transgender person, hiding their transgender status from society after transition.