so cute! very fun tune, brings a smile to my face. indeed, congrats on your first major entry \o/
one thing i think it could benefit from is some decay on the volume of the supporting squarewave lines, esp when they are exposed - both that and just using some note lengths that don't go all the way to the next note. it'd have more character that way and feel less static. i like the supporting lines themselves though, the counterpoint is a nice and welcome detail