Since I listen to a lot of Asian music, I'd love to actually understand what they are saying. So, Japanese, Chinese and Korean are the language on top of my list. And I also love how beautiful Chinese seems on paper. I'd love to be able to write it as well.
I'm half arabic so I do aim to learn it one day but to be honest, I've tried doing that a few times but failed because it's so freaking difficult! My mother speaks it fluently and when she does, it gives us all a headache. It's such a weird language.