Koikatsu Sunshine

The protagonist lives alone near his aunt's house while his parents work abroad. He transfers to a school where he is the only male student among a large female population — an institution his aunt happens to run as principal. Once the strangeness of this arrangement begins to settle, she presents him with a specific mission: use the summer training trip to help the less experienced girls become comfortable with romance. The game follows what happens when that plan is put into motion.