In the first section of the game you will run across a wolf cub in a room. Simply clear the room and interact with it. You will need to find three ingredients to cure the cub. These will randomly generate in future dungeons and if you are completely clearing them you will find them all within a few runs.
For the last ingredient you will have to fight a moderately difficult enemy for your level. Stay close to him and evade his attacks or shoot from afar and dodge his bull rush. The achievment will unlock once you are back at the manor after the cutscene.