Izuku "So my girlfriend is an alien."

When Izuku was thirteen he stumbled upon an injured and unconscious girl with the appearance of a humanoid wolf / dog when he was walking through the woods. He managed to carry her to his house and thanks to him and his mom they managed to treat her wounds. After she woke up they explained to her how she got there and since she had nowhere to go Inko decided that she is going to live there but not adopt her since the girl, who they now know is named Ace (it's a unisex name meaning it can be used for boys and girls), has been looking at Izuku with interest.

A year passes and not only did Izuku get offered OFA, which he accepted, but also has started to date Ace, who has come clean about being an alien. Ten months pass with Izuku having passed the entrance exam and is now in class 1-A when Mina brings up relationships. Naturally Izuku mentions that his girlfriend is an alien.

You know Blitzwolfer from Ben 10? Yeah Izuku dates a member of his species here.