My Friend's Little Sister Has It In for Me!

High school student Akiteru Ooboshi has no interest in the typical pursuits of youth. To him, chasing after fun, building friendships, and even pursuing a romantic relationship are nothing more than frivolous distractions that waste valuable time. He prefers to keep his life simple, efficient, and entirely focused on his own priorities, actively avoiding the chaotic social entanglements that consume most of his peers. However, maintaining this carefully isolated existence proves nearly impossible when Iroha Kohinata, his best friend’s younger sister, makes it her personal mission to disrupt his peace. Rather than keeping a respectful distance, she constantly teases him and invades his personal space with relentless energy. She acts as though his bedroom is her own, casually lounging on his bed and transforming his quiet sanctuary into a whirlwind of clingy, unpredictable behavior. What frustrates Akiteru the most is the stark contrast in her demeanor. Around everyone else, Iroha appears perfectly composed, yet the moment they are alone, she unleashes an exhausting barrage of annoyance directed solely at him. Unable to understand why she reserves this overwhelming attention exclusively for him, Akiteru finds his desire for a quiet, uneventful high school life continually challenged by the one person who refuses to leave him alone.