Saving 80,000 Gold in Another World for my Retirement

Obtain a comfortable retirement with two billion yen and a lovable companion in tow! Mitsuha Yamano, at the age of eighteen, was left to fend for herself after a tragic accident took her family. She found it challenging to plan for her future until a mysterious entity granted her the power to jump between dimensions. How will she employ this gift?
Mitsuha is determined despite her forgetfulness. Equipped with contemporary knowledge and proficiency, she strives to create her wealth in a medieval society full of financial dreams.