Overview
Teenage math whiz Kenji Koiso agrees to take a summer job at the Nagano hometown of his crush, Natsuki. When he arrives, he finds that her family have reunited to celebrate the 90th birthday of their matriarch. His job: pretend to be Natsuki's fiancé. Meanwhile, his attempt to solve a mathematical equation causes a parallel world's collision with Earth.
| Actor | Age then | Age now | |
|---|---|---|---|
 | 16 | 32 | |
 | 16 | 32 | |
 | 19 | 35 | |
 | 63 | 79 | |
 | 44 | 60 | |
 | - | - | |
 | - | - | |
 | 48 | 64 | |
 | 62 | 78 | |
 | 42 | 58 |