Kimi wo Ushinaitakunai Boku to, Boku no Shiawase wo Negau Kimi

is a Japanese light novel series written by Natsumi Kanda, with illustrations by Achiki. The series began publication on January 10, 2020 by ASCII Media Works under their Dengeki Bunko publishing imprint.

Synopsis
"I want So-chan to be happy, so I can't do it."

Summer in my first year of high school. On the day when he finally realized his love, his beloved childhood friend replied. I am destined to become a vegetative state in three years. That's why I want you to be happy with someone other than yourself.

I got the chance to time leap to change my destiny. But it's such a cruel test that every time she fails, she regains all the painful memories.

The whereabouts of the sad love that I can't give up while repeating the bitter ending many times.

I'm sorry, Ichiyo. If you're next to me, I'll help you over and over again.