Maurlene

Maurlene is Grandpa's girlfriend and only appeared in the online version of Diary of a Wimpy Kid. She was replaced by Darlene in Hard Luck. She has cheetah skinned underwear and once left it on chair causing Susan to believe Frank's having an affair with another woman.

Trivia

 * Since Greg says Maurlene looks 20 years younger than Grandpa, she is possibly in her 60s or 50s.