His three lovely neighbors were like big sisters. He longed to embrace them but couldn't say it, so the eldest slipped him a drug to relax. The drug unexpectedly shrunk him from man to boy-size. Now he's cuter than ever! Which of the sister should look after the reduced protagonist? He chooses gentle, buxom Kasumi, and his sweet babymaking life begins!

The cool beautiful middle sister of the three, Kasumi lovingly takes care of you until the drug wears off. More than a sister she dotes on him like a mother! But mama's horny, and now's the time to live out a boyhood fantasy. Fill her deep with man-sized c*ck! She may be cool on the outside but she's warm, wet and sweet on the inside...

Soon he'll be a boy no more... until then let responsibility be damned! Cream her wanton hole with daddy juice!! Make the family that will keep these hot, hot, hot sisters in his life forever!

(Source: dlsite, edited)