diff --git a/lib/github/nippou.rb b/lib/github/nippou.rb
index fff95cd..6a78cd3 100644
--- a/lib/github/nippou.rb
+++ b/lib/github/nippou.rb
@@ -1,4 +1,5 @@
 require 'github/nippou/concern/sawyer_resource_github'
+require 'github/nippou/concern/string_markdown'
 
 require 'github/nippou/commands'
 require 'github/nippou/user_events'
diff --git a/lib/github/nippou/commands.rb b/lib/github/nippou/commands.rb
index ce5cd3c..ba557c5 100644
--- a/lib/github/nippou/commands.rb
+++ b/lib/github/nippou/commands.rb
@@ -1,18 +1,10 @@
 require 'thor'
 
-module StringExMarkdown
-  refine String do
-    def markdown_escape
-      self.gsub(/([`<>])/, '\\\\\1')
-    end
-  end
-end
-
 module Github
   module Nippou
     class Commands < Thor
       using SawyerResourceGithub
-      using StringExMarkdown
+      using StringMarkdown
 
       default_task :list
       class_option :since_date, type: :string,
diff --git a/lib/github/nippou/concern/string_markdown.rb b/lib/github/nippou/concern/string_markdown.rb
new file mode 100644
index 0000000..9ffe2f1
--- /dev/null
+++ b/lib/github/nippou/concern/string_markdown.rb
@@ -0,0 +1,7 @@
+module StringMarkdown
+  refine String do
+    def markdown_escape
+      self.gsub(/([`<>])/, '\\\\\1')
+    end
+  end
+end