I don't have an account yet but your topic is super interesting so I ended up reading through yokai.com for an hour or two. :) I'll be posting as a guest for now and register later.
By the way, I want to mention that my choice is based more on how I interact with other people in general, and less on personal things such as my job or gender or age.
Anyways, a little bit about me. I'm usually the type to fool around with my friends doing stupid things, and I also hesitate a lot with big decisions.
So, what youkai would I be?
I would say I most connect with the Bashou no sei. Bashou no sei are common banana tree spirits. They usually appear as faces on banana leaves, scaring humans by suddenly showing up next to them. They also sometimes take the form of people. Bashou no sei usually aren't hostile, and can be avoided if carrying a sword. There is also a catch, though. They are known to sometimes impregnate women if they walk near banana trees past 6 PM (this part is less connected with me).
Unlike Yumetou (OP), my life as a bashou no sei would be rather unhelpful to the humans of Gensokyo. It might be a bit funny to surprise some passersby, but I would have to be careful not to piss off someone like Reimu and proceed to have all my trees lit on fire by danmaku or something (lol). Basically an irrelevant stage 1 midboss. I would have some more freedom to roam, as I bet banana trees are very common all around Gensokyo. Maybe I would be able to chill out with fellow weakling youkai such as Nightbug and Kogasa. Overall, sounds like a pretty unimportant life but also real fun at the same time!