Adult PC Game: The King of Summer - Version 0.6.2-full by No Try Studios Win/Mac/Android Archive

Satoshi and Mary are a college couple happily in love, ready for their first summer vacation together. One day, Satoshi receives an e-mail from his uncle Kendo, inviting him to spend several weeks with him at the Naval Treasure Resort, a luxurious summer resort, all costs paid. Overjoyed, Satoshi and Mary head over there, ready to enjoy their vacation to the fullest.
And enjoy it they will... for Mary is a beautiful girl, Satoshi a well-meaning but negligent boy, and Kendo a man who thought his days as a manly womanizer were behind him... until Mary awakens something in him that will unleash his desire and lust in every young girl that catches his attention!
A tale of NTR full of seduction, forbidden relationships, and (surprisingly) a happy end!​