Bitch na Inane-sama – Episode 1

His older sister has always been the ultimate overachiever—the type of person who refuses to be anything less than number one in every single endeavor. However, things begin to take a wildly unexpected turn when she decides to apply that exact same fierce perfectionism to their hidden, unconventional bond and her newly awakened, boundary-pushing preferences. Now, her relentless drive to master this taboo territory is starting to push things a bit too far.