I got my inspiration from a commerical. It's just that easy, folks. Another opportunity to learn your Lisa. The real point of the comic is that while Lisa is usually reserved and quiet (Tuff is usually the boisterous one), there's two things that make Lisa, erm, noisy? Excitable? First off, it's competitive video games. Any game with a competitive mode, beatable records or leaderboards, she gets rowdy. Secondly, it's anything she's a fan of. Mega Man, Adventure Time, whatever. She can't contain her geekiness, so she gushes. In school she's better behaved and keeps to herself, but her ears will still perk up.