Hiroyuki Tokumori is one of Yukari Hayasaka's classmates.
He is an intelligent and handsome prodigy who is the object of Yukari's affections at the beginning of the story. Hiroyuki was once in love with Miwako, but Arashi forbade her from seeing him. He gives advice to Arashi on how to come to terms with his feelings for Miwako and his past actions and soon after the three of them mend thier friendship. Hiroyuki is at the top of the class and aspires to become a physician. He eventually falls for Yukari, who foolishly assumed that a girl like her would never show interest in him. In the manga, Hiroyuki expresses his frustration at always being second-place in anything but academic, referring to Miwako choosing Arashi and to Yukari being in love with George. He doesn't have luck when it comes to love.
In the first chapter of the manga, Hiro thinks Yukari is hot.
He was first in love with Miwako but got over her and moved on.
He is the son of Gokinijo Monogatari character Hiroaki Tokumori ("Toku-chan").
Personal Story
After Yukari broke up with George, she and Hiro are shown in the epilogue engaged.