Circuit Heart has always been engrossed in his work. Despite attempts by his best friend, a changeling hybrid by the name of Ebony Runwick, he's never given up his workaholic tendencies. But, when a package arrives at his home it changes everything. Can a simple mail pony really change his heart? Or, will he be stuck the way he is forever? Co-writing with FandomsandfeelsandshipsOHMY