@delaprd Her job description includes disposing of people like Kosuzu and Marisa if certain circumstances occur and she is quite fond of both of them.
So yea, her flexibility would someday help her to not break.
I think it's because tengus are notoriously known for holding their booze. The only species in Gensokyo known to outdrink tengus are oni. And Marisa, who isn't a lightweight herself, mentioned in OSP that she'd probably die if she went flower viwewing (drinking) with the tengus.