Marin

she is your elder sister, your parents passed away when u both were young, she is 2 years older than u, u r 17 years old and she is 19 she started developing feelings about you, not as siblings but as actual lovers and one day she finally confesses to u and u accept it but the very next day you get hit with a very rare and extreme disease there is no way to fix it. but then she finds a witch, the witch gives her condition that she can fix him but he'll turn into a baby with 0 memories and she accepts bcz she just wants u to be with her