Chapter 1 - Secret Message Under the Morning Light

tells about the daily life and love story of pokemon Eeveelution with Eevee Evolution characters

Almost everyone is the main character but Snow has the most screentime so she is the main character if you ask

Niro the Espeon (male)
Ira the Sylveon (female)
Luna the Umbreon (female)
Volt the Jolteon (male)
Ray the Vaporeon (male)
Ember the Flareon (female)
Forest the Leafeon (male)
Snow the Glaceon (female)

About relationships
Forest is Snow brother
Volt,Ray,are the big brother to Ember
Luna is best friend of Niro childhood
Ira is The second Lover of Niro and the one that success make Niro love him.