A wise sage made a prophecy, and the inhabitants of a distant world have been waiting for it to become truth.
Ten years ago, in a dark summer night, Haruto climbs a tree to grab a beetle. Suddenly a bright light makes him fall down.
Haruto approaches the light and finds an adult and a young girl, named Hime, coming out. She greets Haruto and asks him to forget what he witnessed, if he does, she will be her friend from that day onward.
And they actually became best friends, years later, they have grown and attend high school. Haruto’s father is usually working, leaving his son on his own, but Hime and her grandfather usually take care of him.
At school, everyone is aware of Hime, she is clever, has good grades and is beautiful, making other boys jealous of Haruto.
Later that day, Hime asks Haruto to a summer festival, and he accepts without hesitation.
At the festival, Haruto gathers the nerve to confess his feelings for Hime, but before he can do it, she breaks the news that she will move away to a faraway neighborhood.
He attempts to tell her how he feels, however, she avoids the conversation, cutting him off as she thanks him for the memories.
Haruto cannot sleep, and still thinks he must talk to her. Trough his window, he is able to see a strange light and begins to remember the day he met Hime.
Haruto runs to meet with her and sees her being magically transported to another realm where she will get married immediately. He decides to follow his gut and follows her.
Hime is about to kiss a prince when Haruto appears behind them. Suddenly, a monster appears and attacks the crowd, focusing on Hime.
Hime grabs an old ring and hands it to Haruto while kissing him. In her world, this means they have become a married couple, and with the ring, Haruto becomes the knight of the prophecy.
Haruto receives an sword and thanks to the ring powers is able to defeat the monster.
(結婚指輪物語)
