diff --git a/honoka/libhonoka/honokapluginbase.h b/honoka/libhonoka/honokapluginbase.h
index 473058d..f44ee88 100644
--- a/honoka/libhonoka/honokapluginbase.h
+++ b/honoka/libhonoka/honokapluginbase.h
@@ -28,7 +28,7 @@
 #include <scim.h>
 #define Uses_SCIM_CONFIG_BASE
 
-#define HONOKA_PLUGIN_VERSION 8
+#define HONOKA_PLUGIN_VERSION 9
 
 using namespace std;
 using namespace scim;
diff --git a/honoka/libhonoka/preeditor.cpp b/honoka/libhonoka/preeditor.cpp
index d6e37aa..810d29a 100644
--- a/honoka/libhonoka/preeditor.cpp
+++ b/honoka/libhonoka/preeditor.cpp
@@ -387,36 +387,36 @@
 
 
 /*!
-    \fn Honoka::PreEditor::getCommitString()
+    \fn PreEditor::getCommitString()
  */
-const WideString Honoka::PreEditor::getCommitString()
+const WideString PreEditor::getCommitString()
 {
     return commitString;
 }
 
 
 /*!
-    \fn Honoka::PreEditor::setCommitString(const WideString &t)
+    \fn PreEditor::setCommitString(const WideString &t)
  */
-void Honoka::PreEditor::setCommitString(const WideString &t)
+void PreEditor::setCommitString(const WideString &t)
 {
     commitString = t;
 }
 
 
 /*!
-    \fn Honoka::PreEditor::resetCommitString()
+    \fn PreEditor::resetCommitString()
  */
-void Honoka::PreEditor::resetCommitString()
+void PreEditor::resetCommitString()
 {
     commitString.clear();
 }
 
 
 /*!
-    \fn Honoka::PreEditor::isPrintable(const KeyEvent &key)
+    \fn PreEditor::isPrintable(const KeyEvent &key)
  */
-bool Honoka::PreEditor::isPrintable(const KeyEvent &key)
+bool PreEditor::isPrintable(const KeyEvent &key)
 {
     if ((key.code == SCIM_KEY_Return) ||
         (key.code == SCIM_KEY_Linefeed) ||
@@ -426,4 +426,29 @@
     return false;
 }
 
+/*!
+    \fn PreEditor::isThrough(const KeyEvent &key)
+ */
+bool PreEditor::isThrough(const KeyEvent &key)
+{
+    // 喰っておくべきもの。
+    if ((key.code == SCIM_KEY_Shift_L) ||
+        (key.code == SCIM_KEY_Shift_R) ||
+        (key.code == SCIM_KEY_Control_L) ||
+        (key.code == SCIM_KEY_Control_R) ||
+        (key.code == SCIM_KEY_Alt_L) ||
+        (key.code == SCIM_KEY_Alt_R) ||
+        (key.code == SCIM_KEY_Super_L) ||
+        (key.code == SCIM_KEY_Super_R) ||
+        (key.code == SCIM_KEY_Hyper_L) ||
+        (key.code == SCIM_KEY_Hyper_R) ||
+        (key.code == SCIM_KEY_Meta_L) ||
+        (key.code == SCIM_KEY_Meta_R) ||
+        (key.code == SCIM_KEY_Num_Lock) ||
+        (key.code == SCIM_KEY_Caps_Lock) ||
+        (key.code == SCIM_KEY_Shift_Lock) ||
+        (key.code == SCIM_KEY_Mode_switch) ||
+        (key.code == SCIM_KEY_ISO_Next_Group)) return true;
+    return false;
+}
 
diff --git a/honoka/libhonoka/preeditor.h b/honoka/libhonoka/preeditor.h
index daa6fb8..549c3f9 100644
--- a/honoka/libhonoka/preeditor.h
+++ b/honoka/libhonoka/preeditor.h
@@ -92,6 +92,7 @@
     static const WideString getCommitString();
     static void resetCommitString();
     static bool isPrintable(const KeyEvent &key);
+    static bool isThrough(const KeyEvent &key);
 
 protected:
     static WideString text;
diff --git a/honoka/plugins/asciiinput.cpp b/honoka/plugins/asciiinput.cpp
index 1ee11a2..16cdf3b 100644
--- a/honoka/plugins/asciiinput.cpp
+++ b/honoka/plugins/asciiinput.cpp
@@ -233,19 +233,7 @@
  */
 bool AsciiInput::keyEvent(const KeyEvent &key)
 {
-    // 喰っておくべきもの。
-    if ((key.code == SCIM_KEY_Shift_L) ||
-        (key.code == SCIM_KEY_Shift_R) ||
-        (key.code == SCIM_KEY_Control_L) ||
-        (key.code == SCIM_KEY_Control_R) ||
-        (key.code == SCIM_KEY_Alt_L) ||
-        (key.code == SCIM_KEY_Alt_R) ||
-        (key.code == SCIM_KEY_Super_L) ||
-        (key.code == SCIM_KEY_Super_R) ||
-        (key.code == SCIM_KEY_Hyper_L) ||
-        (key.code == SCIM_KEY_Hyper_R)||
-        (key.code == SCIM_KEY_Mode_switch) ||
-        (key.code == SCIM_KEY_ISO_Next_Group)) return true;
+    if (PreEditor::isThrough(key)) return true;
 
     if ((compose)) {
         if (composeKey1.code == 0) {
diff --git a/honoka/plugins/kanainput.cpp b/honoka/plugins/kanainput.cpp
index 1d81d4d..ac5080f 100644
--- a/honoka/plugins/kanainput.cpp
+++ b/honoka/plugins/kanainput.cpp
@@ -188,18 +188,7 @@
 bool KanaInput::inputEvent(const KeyEvent &key)
 {
     // 喰っておくべきもの。
-    if ((key.code == SCIM_KEY_Shift_L) ||
-        (key.code == SCIM_KEY_Shift_R) ||
-        (key.code == SCIM_KEY_Control_L) ||
-        (key.code == SCIM_KEY_Control_R) ||
-        (key.code == SCIM_KEY_Alt_L) ||
-        (key.code == SCIM_KEY_Alt_R) ||
-        (key.code == SCIM_KEY_Super_L) ||
-        (key.code == SCIM_KEY_Super_R) ||
-        (key.code == SCIM_KEY_Hyper_L) ||
-        (key.code == SCIM_KEY_Hyper_R) ||
-        (key.code == SCIM_KEY_Mode_switch) ||
-        (key.code == SCIM_KEY_ISO_Next_Group)) return true;
+    if (PreEditor::isThrough(key)) return true;
 
 
     for(unsigned int i = 0;HonokaKanaInputTable[i].code != 0;++ i) {
diff --git a/honoka/plugins/nicolainput.cpp b/honoka/plugins/nicolainput.cpp
index 1cd016c..2eb5da7 100644
--- a/honoka/plugins/nicolainput.cpp
+++ b/honoka/plugins/nicolainput.cpp
@@ -257,19 +257,7 @@
  */
 bool NicolaInput::inputEvent(const KeyEvent &key)
 {
-    // 喰っておくべきもの。
-    if ((key.code == SCIM_KEY_Shift_L) ||
-        (key.code == SCIM_KEY_Shift_R) ||
-        (key.code == SCIM_KEY_Control_L) ||
-        (key.code == SCIM_KEY_Control_R) ||
-        (key.code == SCIM_KEY_Alt_L) ||
-        (key.code == SCIM_KEY_Alt_R) ||
-        (key.code == SCIM_KEY_Super_L) ||
-        (key.code == SCIM_KEY_Super_R) ||
-        (key.code == SCIM_KEY_Hyper_L) ||
-        (key.code == SCIM_KEY_Hyper_R) ||
-        (key.code == SCIM_KEY_Mode_switch) ||
-        (key.code == SCIM_KEY_ISO_Next_Group)) return true;
+    if (PreEditor::isThrough(key)) return true;
 
 
     map<KeyEvent,NicolaKey>::iterator it = keymap.find(key);
diff --git a/honoka/plugins/romkan.cpp b/honoka/plugins/romkan.cpp
index 2853bdf..5d2d3f6 100644
--- a/honoka/plugins/romkan.cpp
+++ b/honoka/plugins/romkan.cpp
@@ -652,19 +652,7 @@
  */
 bool Romkan::inputEvent(const KeyEvent &key)
 {
-    // 喰っておくべきもの。
-    if ((key.code == SCIM_KEY_Shift_L) ||
-        (key.code == SCIM_KEY_Shift_R) ||
-        (key.code == SCIM_KEY_Control_L) ||
-        (key.code == SCIM_KEY_Control_R) ||
-        (key.code == SCIM_KEY_Alt_L) ||
-        (key.code == SCIM_KEY_Alt_R) ||
-        (key.code == SCIM_KEY_Super_L) ||
-        (key.code == SCIM_KEY_Super_R) ||
-        (key.code == SCIM_KEY_Hyper_L) ||
-        (key.code == SCIM_KEY_Hyper_R) ||
-        (key.code == SCIM_KEY_Mode_switch) ||
-        (key.code == SCIM_KEY_ISO_Next_Group)) return true;
+    if (PreEditor::isThrough(key)) return true;
 
     if (key_a2k.comp(key)) {
         asciiToKana();
diff --git a/honoka/src/honoka_imengine.cpp b/honoka/src/honoka_imengine.cpp
index 4c1fb69..a651385 100644
--- a/honoka/src/honoka_imengine.cpp
+++ b/honoka/src/honoka_imengine.cpp
@@ -1075,18 +1075,7 @@
     // 変換時のキーイベント処理。
     // 喰う！。
     if (key.is_key_release()) return true;
-    if ((key.code == SCIM_KEY_Shift_L) ||
-        (key.code == SCIM_KEY_Shift_R) ||
-        (key.code == SCIM_KEY_Control_L) ||
-        (key.code == SCIM_KEY_Control_R) ||
-        (key.code == SCIM_KEY_Alt_L) ||
-        (key.code == SCIM_KEY_Alt_R) ||
-        (key.code == SCIM_KEY_Super_L) ||
-        (key.code == SCIM_KEY_Super_R) ||
-        (key.code == SCIM_KEY_Hyper_L) ||
-        (key.code == SCIM_KEY_Hyper_R) ||
-        (key.code == SCIM_KEY_Mode_switch) ||
-        (key.code == SCIM_KEY_ISO_Next_Group)) return true;
+    if (PreEditor::isThrough(key)) return true;
 
     // 自動候補ポップアップのカウント計算。
     if ((alp <= alp_count) && (alp != 0)) {