Siege of Black Watch
Tiger companion to Asuna
Orphaned as a cub, Nico was found wandering the forest crying for food; when Asuna Vesta came upon him. Taking pity on the poor creature she fed him and gave him shelter, and they quickly bonded. Soon the two were inseparable, and he joined her on her journey of self. He learned battle strategies, defense, and that above all taking commands from Asuna would keep them both alive as they learned together.
Nico found that he did not age as the other tigers, and found himself stronger and with a longer life due to his bond with Asuna. Taking this as a blessing to remain with the one who had rescued him and whom he loved even longer. Their bond is an unshakable one that breached farther then master and pet.