Sorcerous Stabber Orphen: The Wayward Journey Volume 1 by Yoshinobu Akita

Orphen is a Sorcerer drop-out from the prestigious Tower of Fangs. His journey to save Azalie, a girl he looked up to like a sister, has brought him to the bustling city of Totokanta. Here they are reunited for the first time in five years. But what is the truth behind her monstrous transformation, and just what secrets lurk behind the Sword of Baldanders...?