in a halfshell 

an expression used to add emphasis to something, much like an exclamation point.

Example #1
A: Landon's coming?

B: You don't like him?

A: I fucking hate him in a halfshell.

Example #2
I'd totally do her in a halfshell.

in a halfshell by Chiggers Dudley May 26, 2008

penelope in a half shell

A person who is not afraid to show their inhibitions, while maintaining their corky demeanor.

A penelope in a half shell could be a person who does a sand crab walk as their greeting.

penelope in a half shell by Molly and Bridget August 27, 2008

Oyster in a Half Shell 

Normally, Oyster in a Half Shell is taken to mean a food dish. However, the extended and additional definition of that expression leads to that of the sexual nature. Now, it is also a phrase that denotes when a male ejaculates onto, or, into a woman's palm after she causes such an incident to occur after performing digital sex, or more commonly known as a hand job. Although it is basically understood that this refers to the same regarding prostitution, many non-professional women, married and unmarried, call it the same thing. Boasting by men about the act often occurs, somewhat like a badge of recognition, et al.,.

Hooker After Satisfying a Client: "Wow! He howled when I jerked him off and I ended up with an 'oyster in a half shell'!"

A Conferring Couple After Intercourse: "I loved it, dear! Your 'oyster in a half shell' was great!!" said Linda.

Man Who is a Legend in his Own Mind: "Yeah, I'm the man! Just did that girl. She then rubbed me off. Talk about 'oyster in a half shell'! There was so much cum that she's thinking about suing me because it slid off the sides of her hands and onto her expensive carpet!"

Oyster in a Half Shell by Mike in Aurora, Colorado May 21, 2008