Chobi

One day, a black pillar appeared in the Sea of Japan — a gate that led to another world, used by monsters to invade this world. Dr. Hayakawa, a professor famous for his research in the field of geology, got sent to the other world with his wife Marie. They returned safely, and wrote the book: The Day of Conjunction. Soon thereafter, they left for the other world again. Years…

For the longest time, it's just been the two of them. Kanojo and her cat Daru are inseparable, having grown up together. Now a junior in college, Tomoka — her roommate of a year and a half — moves out of their shared apartment, and in order to keep her living space, Kanojo must find a job. Day by day, Daru watches her continued efforts from a cat's-eye view, eagerly awaiting…