Who does Lisa have a crush on?

Answer 1

From The Simpsons Movie:

Colin is a young environmentalist who has moved to Springfield from Ireland. He falls in love with Lisa, and the film ends with them holding hands. Lisa initially suspects that Colin's dad is Bono since Colin is Irish and states his father is a musician; Colin repeatedly says that his father is not Bono. When asked if he plays instruments, he modestly replies, "Just piano, guitar, Trumpet, drums, and bass." He writes a song for Lisa, but because she cannot hear him through the dome, he writes the sheet music on the dome's surface. At the end of the film Colin and Lisa go on a date.