[flounders]

I'm a lefty as well, and initially my hand would smear the ink as I was writing. I think I had that problem with rollerball pens to begin with, so after I did some research on proper handwriting technique, I learned I needed to hold the pen such that my hand was underneath it much like a right handed person holds it by default. It took some time to adjust but I'm more comfortable writing with any pen now than when I used to have more of a claw grip. Once you get that down, using a fountain pen will never be a problem for you and is far more of a pleasure to write with than most other writing implements will give you.