Doki Doki Family

Goro Kosaka has developed a rare condition that will kill him if he doesn't try to keep his heart rate up. Goro's adoptive family decides to use their bodies!?
For Goro Kosaka, who would die if his heart stopped racing, so begins a sweet life where the heroines constantly shower the hero with love and affection morning, noon, and night.
Mornings with the spoiled little sister... and school with the older sister who works as a teacher... and at home with the beautiful, nurturing mother...

Spending everyday receiving "heart rate management" therapy… such an extraordinary sweet life awaits!

[From Steam]