Aya Hasegawa is like a father of the family towards the children that Diane has. He’s known them for at least three years. But he and Sugoroku Motou are good close friends since he is his assistant when going on archeological digs with him from time to time if he’s not too busy teaching at Domino University as a professor, to go. Sugoroku introduced Aya to Diane and they hit it off as friends in Diane’s opinion but to him, he’d fallen in love with her but was aware that she’d fallen for Gozaburo Kaiba. He knew she wasn’t the type of woman that was after money so in a way he didn’t understand why she loved him.

Aya’s first wife around that time had already died of Leukemia and they did have a child together which they named Tara. He adores his daughter so much and prays that the same thing doesn’t happen to her like it did to her mother. But his wife’s last words to him were to move on with another woman and create a new life while continuing to take care of their daughter. He has sort of an absent minded personality where he tends to be forgetful. Aya can also be quite clumsy as well which also resorts to Diane punching the hell out of him anytime they ended up in uncompromising positions. And he can talk out of line without realizing it by saying something perverted in the form of a compliment which of course still gets him punched the hell out.

So yeah, Diane pretty much hates Aya’s guts but he still loves her anyway. The last time he saw her she threw a ring he’d tried to give her before she left Domino City at his head and told him she didn’t want it. Hopefully if he sees her again he’ll try once more to give her the ring until she accepts it because he refuses to give up in proving to her that he loves her even when she’s still blinded by her love for Gozaburo. But when the Battle City Tournament rolls around the corner, he follows Diane to the tournament in order to get Jasmine away from Kaiba but Aya sees different and thinks that Diane should just tell her children what happened six years ago between her and Gozaburo instead of pushing Jasmine away by yelling at her and telling her that Kaiba is not good enough for her.

But whether or not he ends up with Diane… you’ll have to read the story.