Oliver Aiku

When Aiku was young he wanted to become the best striker in the world but his coach and other adults tainted his dream with the philosophy of "playing for others". He lost the will to become the best striker in the world in time but decided wholeheartedly to become the best defender in the world to spite all the adults and coaches that told him to play for others and refused to help him pursue his own goals. He promised himself though that if a "true striker" ever appears, struggling to bloom in Japan, he will do whatever it takes for them to shine and prevent them from being tainted like he was.

Aiku has been shown to be a womanizer when he invited two girls to karaoke on a date when they did not know about each other. They slapped him and left because of his rudeness assuming they would want to share him but he seems to not be too worried about women.

Aiku lives up to his title as captain as he is the defender and peacekeeper of the Japan U-20 team and its players as seen when he stops Ryusei Shido from harming their Ace and also keeping their Ace and other members in check with his charisma. Despite his seemingly jovial and friendly manner, Aiku changes dramatically when on the field, becoming a dangerous and highly skilled threat. Aiku can be a bit reckless for he unnecessarily bet the fate of him and his team for a chance to beat the Blue Lock Eleven properly and prove something to himself. When the first half of the Japan National Representative is over, Aiku apologizes to his team for his recklessness and decides to play their trump card to prevent them from losing. Aiku also can be quite blunt; at halftime during the Japan National Representative match he states that he wanted to see how strong the team was, and tells the team that they're "weak" compared to the talented players at Blue Lock.

Aiku is not above showing his respect for those who have impressed him as he constantly commented on Blue Lock's ability during the U-20 match and when he congratulated and shook Yoichi Isagi's hand at the end of the match for beating him and scoring an incredible goal. After the game, he seems to have no hard feelings but keeps his competitive nature.