Bowie has to be the instigator in this as she kisses her buddy in a sneaky way and confuses him. When he asks why she kissed him, she simply says "because I like you." Well since Elliott likes Bowie it is only natural for him to want to return the favor. But before you know it, they kiss for real and Elliott could not be any happier. He actually cheers while pumping his fist in the air.
Now that is the sweetest first kiss I have ever seen!