Hyakuren no Haou to Seiyaku no Valkyria

Yuuto Suoh experiences unexpected consequences after participating in an urban legend with his childhood friend. After taking a photo of himself with a divine mirror at a local shrine using his phone, he is transported to a world rooted in Norse mythology. Leveraging his academic knowledge and the capabilities of his solar-powered smartphone, he seeks to elevate the status of the Wolf Clan, who once looked after him. In this new realm, he also gains the favor of a group of warrior maidens who wield magic, known as the Einherjar.