Everyone has a soulmate. How they find them is unique on their own, however it is a rare condition. For example, a pair can see colors when they met each other, a mark or tattoo of a number that indicates the age of when they'll meet their significant other, heterochromia eyes where one eye is the eye color of their soulmate and will change once they meet, etc.
The last just happens to be Shimokaze Yuki's condition. While her right eye is segmental heterochromia or dual-toned, the upper half dark purple and the lower half azure blue, her left is a simple turquoise.
Unfortunately she does not care about love or soulmates, as she is focusing on being a hero. Her first, best, and childhood friend, Midoriya Izuku, seems to be bothered by this but respected her way of thinking nonetheless.
As one of the top U.A. Academy student, being one of the five who went through recommendation course, her personality seems a bit... out of place, so to say. A mysterious young women, who never showed and admitedly never felt any emotions. Not a socially awkward person, but not a distant person as well.
Her classmates of 1-A got used to her strange personality, with the help of Midoriya and her Junior High friend, Iida. Oh, let's not forget Bakugou, who's pretty much stuck up to her, Midoriya, and a certain "Half-and-Half Bastard."
Little did she know, he is her soulmate.