No, he uses it with one-hand but it's actually a two-handed sword.

Biologically? At least a few decades old but still less than a century. Mentally, he's in his twenties but with the memories of Crowley in his head he's much more mature than your average twenty-something-year-old.

You'd be surprised what Vampires perceive as normal relationships. Polygamy would no doubt be a very common thing among Vampires as it'd be a way to spice up the monotonousness of their eternal lives.

And here I am, not being able to post a picture with no nudity when you can post this. Nice pic though. Very cultured.

Striga In Her Day Armor:

Carmilla: