Nationality Japanese

Aoi's uncle, he was living in Italy, and told Aoi to come, that he'd take care of him and introduce him to some clubs there. However, he died and it was his funerals when Aoi arrived. Still, before dying, he talked to a woman about him, who proposed him a boarding house if he could pay a rent (World youth arc, chapter 1, page 8). It'll be revealed later that he wanted to introduce Aoi to the Inter Juniores and their head coach Bassi (World youth arc, chapter 3, pages 2-3).
Conjecture: He was probably funny and excentric. Look at that mustache! End of conjecture.