竜王様の安眠薬~契約から始まる愛~

To fund her dying sister's cure, human girl Elena applies as the Dragon King's 'sleep companion'. Barefoot and fearless, she passes brutal trials, saves the choking matriarch, heals betrayed princess Giselle by exposing Vivian, and tames the violent fourth branch—until ice-cold Arthur, sleepless for twenty years, lets his guard down and finds love.