[Ninniku Batake (Ninniku)] The Black and White in Me (Touhou Project)

Judge of the Dead Eiki Shiki catches her ferrywoman Komachi Onozuka napping carefree in her boat, huge breasts spilling loose from her top — and the strict arbiter's rational white half collapses entirely into something black and hungry. What starts as a flustered stare becomes a full assault, Eiki pinning her subordinate down to greedily worship and bite Komachi's soft tits while the panicked shinigami begs her to stop, demanding to know where her usual rational self went. By the end Eiki is rutting into her with a cock Komachi never saw coming, ignoring her screams to pull it out until a messy splurting nakadashi finish leaves them both wrecked.