The Elder Sister-Like One Vol. 4 (manga)

Haru has been taken captive by Chiyo, and her only hope of escape lies with Yuu and his desperate pleas on her behalf! His persistence pays off, as Chiyo eventually relents, but when Haru decides to stick around, Chiyo's none too pleased with her constant presence in the house. With two demonic "big sisters" to take care of him now, Yuu may have bitten off more than he can chew!