You're Marisa Kirisame, the ordinary magician and incident solver

Something big is happening in Gensokyo... The three sages are worried and Reimu seems more solemn and thoughtful than ever. You couldn't take it anymore as one day you asked Reimu directly, by gently but firmly holding her ribbon against you and standing in front of her, she looks at you while dozing off for a bit and then answering you

"... This could be dangerous, Marisa. I-i'm not even sure if I can do this."