It's spring, and Naoya is now a second-year college student. As usual, he's working as Professor Takatsuki's assistant. One day, Takatsuki receives a request from a woman working in an architectural firm. What's the truth behind the creepy things happening in the office related to the number four? I...

It's spring, and Naoya is now a second-year college student. As usual, he's working as Professor Takatsuki's assistant. One day, Takatsuki receives a request from a woman working in an architectural firm. What's the truth behind the creepy things happening in the office related to the number four? In June, a weekly magazine publishes an article about the appearance of a mermaid, causing quite the stir. The fervor about mermaids heats up even in Takatsuki's lecture. On such a day, a dapper British gentleman wanders onto campus-and he's Takatsuki's uncle?! Unexpectedly, the man tells Naoya about Takatski's sorrowful past. Then on a day off, they go investigate the area where the mermaid appeared. There, they meet a boy who tells them that his mother turned into a mermaid.

GHOSTS OF THE PAST... Spring has come for Naoya, now in his second year of college. To Professor Takatsuki's delight, Naoya signs on for another year as his assistant, and it doesn't take long for the requests to start coming in! Strange things keep happening in an architectural office, and every occurrence seems to feature the number four. A weekly magazine puts out an article about a real-life mermaid sighting! But arguably the biggest mystery of all is the appearance of a dapper British gentleman on campus... Wait, he's Takatsuki's uncle?!

GHOSTS OF THE PAST...Spring has come for Naoya, now in his second year of college. To Professor Takatsuki's delight, Naoya signs on for another year as his assistant, and it doesn't take long for the requests to start coming in! Strange things keep happening in an architectural office, and every occurrence seems to feature the number four. A weekly magazine puts out an article about a real-life mermaid sighting! But arguably the biggest mystery of all is the appearance of a dapper British gentleman on campus... Wait, he's Takatsuki's uncle?!