Lagoon engine - Yukiru Sugisaki

Yen Ragun (age 12), who tries very hard to be the smartest boy in the entire district, is constantly tied with one Ayato Housui. He comes home from school one day only to find that this same Ayato is his cousin and will be living with his family indefinitely. But he doesn't have time to worry about that, because he and his little brother Jin (age 11) are constantly undergoing training to join the family business as Gakushi. Gakushi are people who take care of ghosts, evil spirits, etc. all referred to as Maga. For their training, Yen and Jin get orders from their father and must solve clues in order to complete their mission. This time their orders are to "listen to the voice of the lost soul." Yen and Jin find out about a ghost at the Tatsunami Shrine. While they're investigating, Yen, who has an unusual allergy, has an attack and is taken to the hospital, where he meets Miki Kirishima. She learns that she has been in the hospital for two years with house sickness, and her pet dog died trying to see her.