Dost thou meanest a rose wood pen?
Looks like rose? Smells like rose? Writes with the color of a rose (and if so, which rose)? For the first: Find or make a rose sculpture with a hollow stem that can hold a pen cartridge. Might be easiest to sculpt the rose around an existing pen. For the second: Scented inks do exist, but they're mostly for fountain pens and the like.