Love Hina Again is a three episode OVA that takes place after Love Hina: Spring Special, and thus expands the Love Hina anime story. Keitaro has been accepted into Tokyo University and his sister becomes the new manager of Hinata Inn. The denizens are not pleased with Kanako's rather intrusive and sneaky methods and wish Keitaro would return.
When Keitaro does return, Kanako reveals that he had made a promise with her to run an inn together. Though Keitaro thinks of her as a sister, she does not see him as a brother and her goal is to win his love. (It is not incest since she is his adopted sister.) Naru and Keitaro are nearly torn apart by her efforts, but manage to win out in the end, and be together at last.