Okay, to overexplain this and all other "Aya is a lolicon" jokes, Tengu are traditionally (after Buddhism came to Japan, anyway) shown as liking children. Not in a creepy way, but such that they give the children gifts and help them succeed. In Touhou, this is shown by Aya often being more fond of the young or childish characters than the more mature ones. And then the fandom interprets that as "Aya likes little girls."
Huh?Oh, no. You saw me?So, what kind of curse did you put on them?It's nothing important, but I'll tell you.A curse to kill only lolicons!I went to get a scoop from Alice, who had nailed straw effigies to trees behind the shrine. (by Shameimaru Aya)
