Abby



Abby is a grad student/Cal Tech employee, who Raj and Sheldon  met when they went to the University Mixer. She is good friends with Martha, and becomes Raj's girlfriend for a short period of time.

Characterization
As Leonard and Howard are both off on a double date with Penny and Bernadette, Raj feels lonely, and suggests to Sheldon that they go out and have some fun. After much persuasion and actually giving away his Green Lantern lantern, Sheldon agrees to go with Raj. At the University Mixer, they meet Abby and Martha, where Martha instantly became interested in Sheldon's limited edition Green Lantern lantern and power ring. All four of them head back to Sheldon's apartment, where they are seen playing Guitar Hero (presumably). Raj yet again is interested in going out with Abby, but she will only agree to hang out with him if Martha can come along. Raj bribes Sheldon with his Incredible Hulk hands signed by Stan Lee. As Sheldon and Martha engage in conversation, Abby and Rah make out with each other. Martha later states to Sheldon that "they're getting busy in the living room".