Leeren

"'If there is one way I can bring that bastard back, and that one is through your guts, I will have your guts, Father.' - Leeren's words to Tael Xeno Licht (CT)"

Blood and Guts - Origin
Setanta 'Leeren', often simply called Leeren was a failed experiment at making an homunculi who could feasably protect the people of Genesis when the apocalypse would come, but, as we all know, this ended in a failure and Leeren, who was nameless, was driven into unknowingness into a world he barely understood, with no purpose of his own... Until he found Vult, a mother figure for him, which taught him what he knows, and named him Leeren, for he was empty on the inside. While Leeren grew disgruntled by the idea of his adoptive mother wanting to achieve completion and therefore abandoning him for the return of the one that abandoned him - For he did not know that he did not mean to do such a thing and died looking for him - he rebeled against her when Yoshiya Kiryu challenged him for a duel. Yoshiya then came to give him a proper name - Setanta, which he wears proudly to this day.