Mer-kin are capable of life on both land or water

the offspring of a mermaid (or merman, not to discriminate) and a human being, the mer-kin are thin humanoids who are at home in water and on land. While similar to humanoids for the most part, their breeding makes mer-kin undeniably attractive, magically sensitive, and graceful, as well as curious and a bit absentminded.

Stats: Mana +3, Reflex +3, Luck +3, Charisma +4, Will +1, Awareness -1, Strength -2, Quickness -3, Knowledge -3, Intelligence -2, Toughness -2. Mer-kin are gifted with magic, agile, and comely, but are frail, absentminded, and somewhat overwhelmed by some of the land world.

Anatomy: very much like their human lineage on the outside, a mer-kin's true differences come into play when water is involved. They have a nearly invisible but very solid webbing between their toes, which give them swift swimming speeds, and their lungs are unlike any other creature's. They are large and can store oxygen for long periods, while their body only demands small amounts to get by. Their lungs also have a powerful filtration system, allowing them to extract air from nearly any conceivable environment. Toxins, water, smoke and so on have little affect on a mer-kin's breathing, as they can draw the little air into their lungs, remove the foreign materials, and use the small amount of air to get by. Mer-kin also have very mild psychic powers, generated from a magical sense inherited from their merfolk parentage.

Genders: mer-kin have largely the same outlook on the world, regardless of gender. They mimic humans to learn more about them, and seek friendship and love however they can. This tends to bring out certain traits in each sex that they use to provide an allure to the opposite sex, based on their understanding of people. Males tend to act chivalrous, brave, and romantic, while women try to come across as frail, helpless, and easily flustered. These do not necessarily express their true personalities, only how they make themselves perceived. Females are only able to become pregnant for a few days every few years, though males can impregnate women at any time (all their kin will be mer-kin, regardless of their partner).

Youth: mer-kin are born of their mothers, as is expected. This can create some difficulty, as a mer-kin must spend a large part of its early life in water. This is little trouble for a mermaid mother, but a human woman who has bred with a merman may find difficulties. Their child will grow ill and die over a few weeks if not brought to the sea, or a large tank in some unusual cases. Most often, these children are simply left to the local mermaids, who will raise it as their own regardless. Mer-kin spend their time mostly learning to swim and hunt fast enough to match their full-blooded merfolk company. They can usually accomplish this after about ten years, and will then be gradually introduced to walking on land if they have not reasoned or attempted this themselves on islands or reefs. When in their later teens, they are encouraged to search the world of the surface and learn about their other half of their lineage.

Mer-kin curiosity gives them an urge to try everything once

Diet: mer-kin are very much like humans, and so can eat any normal foods normally. They do find that while on their time on the surface, they discover a craving to try many different dishes. Some believe that they will not stop this practice until they have tried what they believe to be everything. Mer-kin can have surprisingly high appetites for their slim and attractive appearances.

Names and Language: mer-kin share the naming and languages of humans and merfolk. They will normally favor common speech, but will often apply mermin if they encounter another with the language available to them, like another mer-kin or pure merfolk.

Territory: mer-kin are too scattered and short-numbered to form many cultures or claim any land as their own.

Psychology: mer-kin feel slightly alienated while also slightly aloof. They realize they don’t quite fit in, even if it is for the general better. They are relatively indiscernible from humans, save for a generally fairer/handsomer appearance. They will often use this to their own designs, either for company or simple manipulation to get what they’re after. Mer-kin often have romantic minds, being raised by their merfolk parents who had to explain how they came to be different. This involves many excuses involving romance and the general free nature of merfolk, which leads to a general disregard for the emphasis other races put on sex. Mer-kin are also only able to become impregnated for short periods every few years, which only furthers this concept.

Technology: mer-kin are sometimes curious of technology, but rarely dedicate themselves to it. They are extremely creative, but have little concern for creating weapons when they could be painting instead.

Politics/Law: having no apparent culture of their own, mer-kin value friendship over most other things. Their free spirits also have limited understanding or respect for law, though they rarely are mean-spirited enough to encounter this as a serious problem.

Religion: mer-kin obviously favor the sea goddess Morlai, who sees them as beautiful creatures of her sea. They may also seek the protection of the earth god Gode while on land, or Shass, Walure, Morlai, or Purill for their general agreement with their outlooks.

Oh, that's right. Mer-kin can swim...

Entertainment: mer-kin have a natural fondness for the arts, particularly music. Mer-kin will rarely find good enough reason to avoid a party, and will almost be guaranteed to join in any chance to dance. They simply adore any reason to celebrate, while quieter times may lead them towards practicing art, song, or poetry on their own. And as already emphasized, they have little worry or unobtainable want for sex.

Interspecies Relations: mer-kin, while seen as somewhat ditzy and womanizing/manizing (?), are seen as relatively harmless. Some are suspicious of their irresponsible nature while others welcome it, but some well-placed charm see to it that mer-kin rarely have trouble finding friendly lands.

Warfare: mer-kin have extremely little want for war, and will ordinarily avoid it entirely. And seeing as their specialty is in water, they are only sometimes bought into employment by marine solders. They are unmatched around water aside from their pure merfolk heritage, employing knowledge and weaponry exclusively specialized for the water to utter baffle opponents.