The best portrait lens I've ever used, but with three "buts" — the Fuji GF 110mm f/2 - Photofocus
Fujifilm GF 110mm f/2 4-Years Later (Review) - YouTube
Amazon.com : Fujifilm FUJINON GF 110mm F/2 R WR LM Lens for GFXMedium Format System - Bundle with Hoya NXT Plus 77mm HMC UV Filter, Hoya NXT Plus 77mm HMC Circular Polarizer