ATID-660 A big sister at the adult recluse support center who responds with a smile no matter what. Miisono Wakaba.

Sent to the home of Sei, who has been shut in his room for years and cut off from society, is Yumi, an employee of the reclusive support center. 'You hypocrite, you're here for the money, aren't you?! I can't trust you!' 'I'm on your side, Sei. Believe me.' 'Then strip naked and clean! If you do that, I'll believe you.' '...Alright. "So you'll believe me then?" Gradually opening his heart to Yumi, who smiles and agrees to any unreasonable demand. Drawn to Yumi's enveloping maternal nature, he experiences a real woman for the first time, unleashing his lust...