Shukuyō (27 Lunar Mansions) (宿曜道)

Japanese Shukuyō (宿曜道) — the esoteric-Buddhist astrology of the 27 lunar mansions that Kūkai (Kōbō Daishi) brought from Tang China, the missing sibling of the Arabic manāzil (28) and the Vedic nakṣatra (27). Your 本命宿 (birth mansion) is the mansion the Moon occupied at birth — one of 27 equal 13°20′ stations — computed by the true sidereal-Moon method (equivalent to the Vedic janma-nakṣatra, on the Lahiri frame); the traditional Japanese almanac method can differ by ±1 mansion, disclosed via a confidence/boundary flag. Each mansion carries its 宿 character and reading, its corresponding nakṣatra, its 七科分宿 nature (安住/和善/急速/軽燥/悪害/猛悪/剛柔), its 七曜 planetary/weekday ruler, and a character sketch. Its signature layer is the 三九の秘法 COMPATIBILITY: give an optional partner and it returns the directional relationship between the two mansions on the 27-ring (命/業/胎 and the 栄衰安危成壊友親 cycle), each person seen through a classical mirror-paired lens, with auspicious/cautionary/karmic valence. Deterministic on the shared Meeus ephemeris and gold-locked against Vedic janma-nakṣatra anchors (Einstein → 心宿, Michael Jackson → 室宿). A symbolic esoteric-Buddhist tradition for reflection — not a validated predictor; no medical/financial/legal advice, no lifespan.

Cost: 3 TIAN Points per call. tRPC procedure shukuyo.calculate.