Kataha no Sakura

Overview

One day, a lord of the spirit world is gravely injured, but he was saved by the scion of a merchant family, Kageaki. In return, Kageaki is gifted a celestial maiden, Juju, who lays eggs that is said to be able to cure any disease… So in order to save his sickly little sister, Kageaki must inseminate Juju time and time again. Kageaki felt guilty about forcing himself on her… but he eventually becomes genuine attracted to the maiden. Likewise, while unwilling at first, Juju cannot resist the pleasure of sex and yearns for more. A pure-love tale about two people coming together under awkward circumstances. (Source: Pillow, translated)

Source: AniList