TypeError after starting

[Fuuzetsu]

✗ 1 misaki shana % ruby bin/ahoviewer 
/tmp/ahoviewer/lib/ahoviewer/booru/site.rb:236:in `[]': no implicit conversion of String into Integer (TypeError)
        from /tmp/ahoviewer/lib/ahoviewer/booru/site.rb:236:in `block (2 levels) in get_tags'
        from /tmp/ahoviewer/lib/ahoviewer/booru/site.rb:236:in `each'
        from /tmp/ahoviewer/lib/ahoviewer/booru/site.rb:236:in `block in get_tags'

Disclaimer: I have no idea what I'm doing when it comes to Ruby. Perhaps I'm running it wrong.

[Fuuzetsu]

Oh, I should probably mention my Ruby version:

ruby 2.0.0p247 (2013-06-27 revision 41674) [i686-linux]