Definition of 上品ぶる
-
(v5r) to give oneself airs; to be prudish
自分よりも下品な相手は『下品』と思い、自分よりも上品な相手は『上品ぶっている』と思いますね。
You think someone coarser than you is "crude", and someone higher class than you to be "putting on airs".