/usr/ is in ruby-net-irc 0.0.9-3.
This file is owned by root:root, with mode 0o755.
..
/usr/lib/
/usr/lib/ruby/
/usr/lib/ruby/vendor_ruby/
/usr/lib/ruby/vendor_ruby/net/
/usr/lib/ruby/vendor_ruby/net/irc.rb
/usr/lib/ruby/vendor_ruby/net/irc/
/usr/lib/ruby/vendor_ruby/net/irc/pattern.rb
/usr/lib/ruby/vendor_ruby/net/irc/server.rb
/usr/lib/ruby/vendor_ruby/net/irc/client.rb
/usr/lib/ruby/vendor_ruby/net/irc/client/
/usr/lib/ruby/vendor_ruby/net/irc/client/channel_manager.rb
/usr/lib/ruby/vendor_ruby/net/irc/message.rb
/usr/lib/ruby/vendor_ruby/net/irc/constants.rb
/usr/lib/ruby/vendor_ruby/net/irc/message/
/usr/lib/ruby/vendor_ruby/net/irc/message/modeparser.rb
/usr/lib/ruby/vendor_ruby/net/irc/message/serverconfig.rb
/usr/share/
/usr/share/rubygems-integration/
/usr/share/rubygems-integration/all/
/usr/share/rubygems-integration/all/specifications/
/usr/share/rubygems-integration/all/specifications/net-irc-0.0.9.gemspec
/usr/share/doc/
/usr/share/doc/ruby-net-irc/
/usr/share/doc/ruby-net-irc/examples/
/usr/share/doc/ruby-net-irc/examples/mixi.rb
/usr/share/doc/ruby-net-irc/examples/echo_bot.rb
/usr/share/doc/ruby-net-irc/examples/hig.rb
/usr/share/doc/ruby-net-irc/examples/wig.rb
/usr/share/doc/ruby-net-irc/examples/lig.rb
/usr/share/doc/ruby-net-irc/examples/lingr.rb
/usr/share/doc/ruby-net-irc/examples/client.rb
/usr/share/doc/ruby-net-irc/examples/hatena-star-stream.rb
/usr/share/doc/ruby-net-irc/examples/ircd.rb
/usr/share/doc/ruby-net-irc/examples/sig.rb
/usr/share/doc/ruby-net-irc/examples/tig.rb
/usr/share/doc/ruby-net-irc/examples/gmail.rb
/usr/share/doc/ruby-net-irc/examples/2ig.rb
/usr/share/doc/ruby-net-irc/examples/2ch.rb
/usr/share/doc/ruby-net-irc/examples/iig.rb
/usr/share/doc/ruby-net-irc/README
/usr/share/doc/ruby-net-irc/changelog.Debian.gz
/usr/share/doc/ruby-net-irc/copyright