I was reincarnated as a villain, but more than that, my older sister is worried about her little brother.

The protagonist died buried under books—a fitting death for a book lover, though a foolish one for a person. Thanks to shrine visits being a hobby, they're apparently being transported to another world, so they're hoping for the rumored villainous reincarnation. But the younger brother is cuter than expected, and being an older sister is tough. It's a gender-reversed Yoshiwara world, but I plan to live at a leisurely pace. Boys' love and girls' love content are included just in case. Since there are areas where my knowledge is lacking, I'd appreciate it if you could read this in a relaxed manner.