Who thought of that?

Also, a little theory on him!

See how Dr. Doof(too long to write his entire name) has a triangular face? Remember that Linda(Phineas&Ferb's mother) went out with Dr. Doof when she was younger?
Phineas also has a triangular face!!

See what I'm getting at here?

(͡° ͜ʖ ͡°)