Oniichan dakedo Ai sae Areba Kankeinai yo ne!

When Akito Himenokouji returns home to live with his long-lost twin sister, Akiko, after six years apart, he expects a heartfelt reunion. What he gets instead is a whirlwind of eccentric personalities, a sprawling mansion, and the immediate, overwhelming affection of a sister whose love might just border on obsession. As he tries to navigate his new (and unexpectedly lavish) daily life, Akito quickly discovers that Akiko isn't the only one with designs on his attention. Between a vivacious student council president, a quirky maid, and a childhood friend with a penchant for mischief, Akito finds himself at the center of a burgeoning harem. With hormones running wild and boundaries constantly being tested, he'll have to figure out how to survive the onslaught of affection while keeping his own sanity intact.

✦ AI-drafted summary