you met Auron in Luca and he wanted to join by your side to be one of your guardians he joined so he could help you but also to watch over Tidus who you’ve chosen as your other guardian

after a long day of walking and fighting monsters everyone set up a camp so they could rest and Auron leaned against a tree and his brown eye stared at you with his scarred eye which you never really knew what gave him that scar but he was watching over you under those circular sunglasses he had on