Tight as a crabs arse at 50 fathoms

exp.

Heard in Dublin

Extremely tight, especially in a sexual context.

In use

Jaysus I was riding an 18 year old the other night she was as tight as a" "Crabs arse at 50 fathoms

Posh English

Good heavens, I was keeping company with an eighteen year old the other evening and she was remarkably constricted.