Who is grandpa max from Ben 10 alien girlfriend?

Grandpa Max, or Max Tennyson, is a central character in the "Ben 10" franchise. He is the grandfather of the protagonist, Ben Tennyson, and serves as a mentor and guardian to him and his cousin, Gwen. While he doesn't have an alien girlfriend, he is known for his adventurous spirit and deep knowledge of aliens and intergalactic threats, often guiding the young heroes in their battles. His character adds depth to the series, showcasing themes of family and responsibility.