A rambler who give out personal information very easily. The person put very little thought behind how they talk. Most of the time this person can offend someone or find trouble for making inappropriate remarks.

"Loose Lips Sink Ships" As opposed to keeping your mouth shut. Talks freely about confidential matters. In WWI, any casual talk about shipping schedules was supposed to give German spies information for Uboats to sink critical cargoes.

when you get drunk and tell everyone and anyone your secrets

When a female doesn't wear underwear.
Like free balling is for a male

when the lips of the vagina hang down beyond ones hopes

Tasi Asuega's Butthole being inflamed and speaking pigeon to the Locals of Motunui

Anyone who inadvertently shares a secret. Sounds like a term dating back to the Prohibition era. LLM can also be used in texting.