Touhou: Fate of External Boundaries

A long time ago in a mysterious land isolated from the human eye, there was an incredibly powerful youkai considered as the chaos goddess. She fought the sages of Gensokyo with the purpose of breaking the Great Barrier containing this land and escaping to the outside world. After a long struggle, the sages of this magical land managed to seal her forever. But in present-day, a boy got lost walking through a forest and ended up entering the Great Barrier without realizing it. The powerful goddess became aware of his presence and took control of his body to help him fight other magical beings with an absurdly powerful ability, lightning. Her goal is to team up with the boy so he could free her from her seal and escape Gensokyo to the outside world.