Oniichan wa Arisu-kun ni Yowai

Yusei's a college student who dotes way too much on his younger sister Miyako!! One day, he meets Arisu, a friendly, handsome young man who's close to his sister. Thinking Arisu was a phony, Yusei's surprised when they go out for drinks and find they get along. The next thing he knows, though, they're in a hotel room together.. Arisu suddenly transforms into a black-hearted hottie!! Arisu gets Yusei off, then takes pictures to use as blackmail! He won't show Miyako, so long as Yusei becomes his boyfriend.