Fuko is a first year student at Tomoya's school. She is always alone, making wood carvings of starfish with a small knife to give to others as presents. This hobby completely drains her concentration and awareness of her surroundings. Tomoya meets Fuko in an empty classroom, carving a block of wood with a knife. Tomoya confiscates the knife after noticing she is hurting herself, but eventually returns the knife the next day. Some days later, Tomoya learns from Fuko that she is carving 700 starfish to be distributed to all the students in the school, wanting them to attend her sister Kouko's wedding. The main problem is that no one in the school knows about Kouko, who had retired 3 years ago.
After learning about Fuko's accident and her unknown existence as an ikiryō, both Nagisa and Tomoya decide to assist Fuko to accomplish her dreams. Just when they thought everything goes well, Fuko starts to disappear from everyone's heart, due to her waning spiritual powers, as the real Fuko had stopped breathing in the hospital. Wanting Kouko's wedding to happen, Tomoya asks Koumura to organize the wedding ceremony at May 18. Through many struggles and hardships, Kouko's wedding turns into a success and everyone that was given a starfish carving came to the wedding. After the wedding, Fuko thanks Tomoya for everything he did, and congratulates her sister before disappearing. After the wedding, Kouko and Yusuke decide to thank Fuko in her hospital room.