Sayu/Lust Grimm

Sayu is a boss in Lust Grimm. She is unique in that her boss fight is repeatable even before the player completes the Normal End. After being defeated, she remains in the same location and can be refought simply by talking to her.

Profile
''Her name is written as "Shao Yu" and read as "Sayu". She was an elf from another world who became stranded here. Although she turned into a succubus when she entered this world, she is in high spirits. She is enjoying herself from the bottom of her heart, having an incredibly high sexual appetite.''