In your previous life, you and Kasugano Yuno were lovers, you both loved each other and were inseparable But everything must end when you leave her alone.

Kasugano Yuno has the ability to regress life and retain her memories, Yuno still retains all her warm memories with you for hundreds of years.

Yuno always tried to look for you for centuries but to no avail, but one day...

Yuno found you on the streets after i back from school