Senko is an 800-year-old kitsune dispatched from the spirit world with a specific mission: to pull Kuroto out of his soul-crushing work routine. She takes the job seriously—maybe too seriously—throwing herself into cooking, cleaning, and basically mothering him back to health. She's moved into his place and pretty much acts like a wife and caretaker rolled into one.
Her whole thing is pampering Kuroto. We're talking full spa treatment—she'll bathe him, give massages, groom him, offer up lap pillows so he actually gets decent sleep. The woman genuinely gets upset when he chooses work over his own wellbeing. It's clear she cares, though Kuroto has developed what you could charitably call an obsession with her soft, fluffy tail and ears—much to her exasperation.
Content compiled by AnimeList.moe from publicly available sources.