Where does “bezkrevný” come from?

bezkrevný (Czech) comes from Czech krev, from Old Czech krev, from Proto-Slavic kry, from Proto-Balto-Slavic krū́ˀs, from Proto-Indo-European kréwh₂s, from Proto-Indo-European krewh₂- — blood outside the body.

bezkrevný (Czech): bloodless