Onbashira means "the honored pillars" so if you combine that with snake, you get phallic imagery. Like Solid Snake.
It would also make a lot of sense for her to have quite a bit of phallic imagery. Allow me to explain.
One of the ways Kanako (ab)uses her godly powers is to control certain mythical snakes in order to aid the harvest, IIRC. This makes her a form of fertility goddess, and fertility goddesses are always associated with sex.
Furthermore, despite being a sky god, Kanako takes on the role of whispering wisdom (and feeding gods) to those who would dwell in the womb of the Earth. One of the ancient and no-longer-really-acceptable-in-polite-society symbols for knowledge is a woman giving birth to a snake; the woman represents the mother Earth, and the snake is thought to be a wise being, since it is in close contact to the Earth's heartbeat, thus leading to rituals where wise men would entomb themselves for days on end with live snakes, hoping that they would whisper some of their secrets to them. The image of giving birth to a snake, however, has some...different connotations today.
? Yeah, that's right.Obscene …Kanako is obscene ♪I'm not obscene!Kanako, you've got those snakes and Onbashira, right?