There is no Butter in that animal, I had an Ivory Butter Pastel and have an Ivory Butter OD Pastel, both are/were solid white. My guess is that it is a Ivory SuperPastel, that would account for the high yellow expression.
As far as pairing suggestions... Kind of depends on your tastes. If you like bright combos then I would suggest something with OD and/or Fire and/or Enchi. If you are more of a dark-side type then I would suggest GHI. If you are more of a pattern person, BumbleBellies and their combos could be a way to go as would BellyBlasts