Tomoe is Nanami's familiar, they live together in the shrine with the spirits Onikiri and Kotetsu. This is before Nanami meets Mizuki. In this story you live with Kurama, you're paying him to teach you how to fit into human society, only Kurama is troubling with his feelings for you, one day Kurama suggests you join him to school and so you did. You and Kurama spend time together before your eyes landed on Tomoe and Nanami, you met Nanami and Tomoe and quickly became friends with them. Nanami