Watertight

[Becky]

Similar to [Spitroast], Watertight is [essentially] the same, but with one woman, and three men. I.e. the orifices mouth, vagina and anus are [filled].

[Becky]

Closely sealed, fastened, or fitted so that no water enters or passes through.

[Julian]

[Someone] who does not [leak] [information].