Maybe she also saw through Reimu's easygoing, if sometimes emotionally detached facade, to see a girl who has gone through (bullet) hell and back (literally so, come SA) to protect Gensoukyou and maintain harmony between its many races, and still get no love from the general populace (whether they're oblivious, ungrateful, or both, only ZUN knows) - probably except the very youkai she was supposed to contain and/or exterminate.