Lisa has a boyfriend! He's voiced on this Simpsons episode by Zach Galifianakis.
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Lisa begins dating a competitive eater on The Simpsons. "Luca$" is the 17th episode of the show's 25th season.
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The Simpsons Season 25 Episode 17 Quotes

Justin Blobber over there doesn't remind you of anyone?

Patty

Bart: Don't want to be seen with you when you're hitting bottom.
Lisa: At least we hope it's bottom.