Tokubetsu Settai ~Gokuraku Joudo e Youkoso~

Main character graduates from the National University and has all doors open before him, but he actually has to inherit hot springs resort after his father. On his hidden side he likes to prey on women. When a family of four people - mother and three daughters - arrive to the resort, he makes sure to prepare all his devices and traps to provide an enjoyable pastime.

[From vndbreview]