I really don't know. There are so many manga out there. Yuki's choice could be anything from a fantasy epic to a slice-of-life story. Maybe you can look for manga-related items around Yuki to get a clue.
Makoto often plays a complex and significant role. Sometimes a protagonist, sometimes a supporting character, but always influencing the plot in important ways.
Makoto Shinkai was a well-known Japanese animation director and producer. His works were famous for their exquisite graphics and deep emotional expressions. The following are some of Shinkai Makoto's selected works:
"5 cm per second"(5 cm per second): This is a 1997 animated film that tells the story of two young people from high school to university and then after they separated. It is known as one of Shinkai Makoto's masterpieces.
2 Your Name: This is a 2016 animated film about two young people who meet each other through dreams and explore each other's identities. It has received widespread praise worldwide.
3 The Star-Chasing Child (The Old Man Who Makes Children's Names Unsettled): This is a 2012 animated film about a young mother and her child who come to a mysterious place to meet and interact with some mysterious characters.
4. Nausica no Kaede (Nausica no Kaede no Nausica): This is a 1994 animated film about an environmental problem. It is one of Makoto Shinkai's masterpieces.
Castle in the Sky: This is a 1997 animated film about a pair of young people exploring the Castle in the Sky.
These are some of Shinkai Makoto's selected works, each of which has its own unique style and theme.
It depends on your tolerance for spooky things. Some people find any ghost story scary, while others might not be as affected. The way the stories are told, the atmosphere created, and the specific elements in the Yuki Ghost Stories all contribute to how scary they are.