Because I Don't Like My Big Brother At-All--!!

Season 1, Episode 6: My Brother has Dreams of Black Panty Stockings

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After having Iroha spy on Shūsuke and Mayuka the previous night, Nao tries putting on black pantyhose and clinging onto Shūsuke as he sleeps. Iroha and Mayuka later arrive, leading to an awkward confrontation. Mayuka ends up questioning what Nao and Iroha see in a pervert like Shūsuke, mentioning her affection towards him is different from theirs. Later that night, Mayuka gets Shūsuke to read through one of her BL books, which ends up traumatizing him.