The Ki-rin (mythologically spelled Kirin or Qiling) is a unicorn-like celestial being from East Asian mythology, a chimera-like creature that blends elements of an Oriental Dragon with the body of a hooved animal and other fanciful aspects. It may have one or two horns, which usually look like the antlers of a deer. Originating from Chinese mythology, it thought to be a symbol of luck, good omens, protection, prosperity, success, and longevity; it is also associated with fertility, and said to presage the birth and/or attend the death of great emperors and sages.
According to Taoist mythology, although they can look fearsome, qilin only punish the wicked, thus there are several variations of court trials and judgements based on qilin divinely knowing whether a defendant was good or evil, and guilty or innocent, in ancient lore and stories. In Buddhist influenced depictions, they will refuse to walk upon grass for fear of harming a single blade, and thus are often depicted walking upon the clouds or the water. As they are divine and peaceful creatures, their diets do not include flesh. They take great care when they walk to never tread on a living creature, and appear only in areas ruled by a wise and benevolent leader, which can include a household. They can become fierce if a pure person is threatened by a malicious one, spouting flames from their mouths and exercising other fearsome powers that vary from story to story.
In /tg/ circles, Ki-rin are most associated with Dungeons & Dragons, having appeared all the way back in 1976's Eldritch Wizardry - it's this game that gave them the distinctive hyphenated form of the name used here. Ki-rin are an iconic Oriental Adventures type monster, although ironically the creature only appeared in the pages of that splatbook once, during the days of Dungeons & Dragons 3rd Edition; in Advanced Dungeons & Dragons, it appeared in the original Monster Manual for 1e, and then in the Monstrous Compendium Volume 2 (and Monstrous Manual) for 2e, with a psionics-using variant in the Complete Psionics Handbook, and skipped 4th edition before returning in 5th edition's Volo's Guide to Monsters.
The D&D ki-rin is a mystical being, resembling a dragon-scaled unicorn with a single deer's antler in place of the horn. It has multiple magical abilities, most notably the power to walk on air as if it were solid, and they vary between being magical beasts or celestials depending on edition. In AD&D, they are capable of shifting to the Ethereal Plane and the Astral Plane at will, whilst from 3rd edition onward they are denizens of the Upper Planes. They are an enigmatic sapient race, who concern themselves primarily with battling evil. They have their own deity, introduced in Monster Mythology: Koriel.
Fun fact: An ancient Chinese explorer of the Ming dynasty Empire named Zheng He once traveled to East Africa in search of Qiling. The mythical beast turned out to be Giraffe of all animal. Yes. The long neck yellow animal that eats tree's leaves was the legendary mythical beast.