A romantic comedy that revolves around a handsome boy, a beautiful girl, and a person in a stuffed animal costume.

From LuffyNoTomo:

Hakka is a normal girl who's life gets turned around when an invader comes from another planet and large stuffed animals have come to protect the world from invasion. She, among others are chosen to be the guardians and team up with these stuffed animals to save the world! One strange thing other than them being stuffed animals, is that when the guardian and stuffed animal kiss - the stuffed animal turns into a handsome man!

It's the Meiji Era in a slightly alternate Japan, and the Gregorian calendar has just come into effect. The fox-eared girls living in the youkai part of town are about to be put to work together with a delegation of young human soldiers, to promote interracial understanding. So what will happen when Zakuro's strong personality collides with human sensibilities?
(Source: MU)

Princess Olga has been putting off her marriage for a long time by setting her suitors to impossible tasks and requiring rare gifts. What she loves most of all are magic objects and one day she discovers a bracelet which allows her to slip into a different world. That world seems to be very different from hers, but it turns out she had more in common with the bronze-skinned princess Abed than she originally thought.
(Source: Aerandria)

Another take on the little mermai...merman?