Kamigami no Asobi

Synopsis

Balder grows more attached to Yui because of her uniqueness in not being affected by his natural charisma as the Norse God of Light. As the season changes once again to winter, Yui and the gods decide to create a cultural festival based on Christmas, splitting into groups based on their heritage. Since Yui is Japanese, she has to work with the Japanese gods, much to Balder's jealousy. He drags her around with him everywhere, until Loki is absolutely frustrated, confronting his friend about a promise they made as children to always stay together no matter what, believing that Yui is coming between their friendship.

(Source: Wikipedia)