Well, despite the simplicity of this piece, I love the animation, as well as how it captures that Phineas-like emotional optimism through both the quote and your facial expressions. On animation, I'll start out by saying that your lighting technique is flawless. That's right - flawless. The light source from the background makes a perfectly realistic shadow on both the ground and your bodies. Nice shiny effect on the eyes, belt buckle, etc., too.The clothing is well-detailed, I might add; soft folds and creases lookin' good. You also stayed pretty true to the Phineas and Ferb animation style, despite slight personalization of it to fit your experiment (which turned out incredibly good, by the way ). You two also nicely convey heartwarming smiles that complement the mutually innocent joy of being together. The cherry on top of all of it is in the quote of choice -
"...there's a world of possibilities..."
Great job, my friend. Incredible execution of all present artistic techniques at your disposal. God bless, peace be with you, and Godspeed in all your endeavors!
I sometimes loosely use the term "animation" when referring to the style of the way something is drawn, usually with respect to TV shows and movies. Eh, but whatever. You're most welcome for the critique.