A long distance girlfriend known only through digital communications, the entire relationship consists of phone calls, text messages, and sent photos. Usually rocky, though not lacking in emoitional intensity or committment due to lack of any physical contact. The relationship is maintained though constant communcation, most often a cell phone in speaker mode, worn in one's pocket to continue interaction with the pocket girlfriend while in public social situations
"who is he talking to?"
"his pocket girlfriend"
"Justin, your pocket girlfriend is a dipshit, you should just get a regular girl here."