diff --git a/dlibrary/dlibrary.py b/dlibrary/dlibrary.py
index d345974..c4dbfba 100755
--- a/dlibrary/dlibrary.py
+++ b/dlibrary/dlibrary.py
@@ -25,6 +25,7 @@ FANZA_ID_REGEX = re.compile('^d_[0-9]+$')
 FAKKU_ID_REGEX = re.compile('.*_FAKKU$')
 
 TEXTLESS_REGEX = re.compile('(台詞|セリフ)(な|無)し|notext|textless')
+ALT_VERSIONS = ['褐色', '日焼け']
 
 IMAGE_FILE_EXTENSIONS = ['.png', '.jpg', '.jpeg', '.gif', '.tiff']
 
@@ -196,24 +197,59 @@ def complete_prefix_number_ordering(entries):
     if len(entries) == 1:
         return entries
 
+    entries_by_version = {}
+    for entry in entries:
+        version = next(ver for ver in (ALT_VERSIONS + ['']) if ver in entry.name)
+        entries_by_version.setdefault(version, []).append(entry)
+
+    numberings_by_version = {ver: prefix_numbering(entries_by_version[ver]) for ver in entries_by_version}
+
+    unified_indices = set()
+    for numbering in numberings_by_version.values():
+        if numbering is None:
+            return None
+        unified_indices |= set(numbering.keys())
+    unified_indices = list(unified_indices)
+    unified_indices.sort()
+
+    versions = list(numberings_by_version.keys())
+    versions.sort()
+
+    version_lengths = {ver: len(numberings_by_version[ver]) for ver in numberings_by_version}
+    inner_versions = []
+    outer_versions = [versions[0]]
+    for ver in versions[1:]:
+        if version_lengths[ver] >= version_lengths[versions[0]] - 2:
+            outer_versions.append(ver)
+        else:
+            inner_versions.append(ver)
+
+    result = []
+    for out_ver in outer_versions:
+        for i in unified_indices:
+            for ver in ([out_ver] + (inner_versions if out_ver == versions[0] else [])):
+                entries_i_ver = numberings_by_version[ver].get(i, [])
+                if len(entries_i_ver) <= 1:
+                    result += entries_i_ver
+                else:
+                    return None
+    return result
+
+def prefix_numbering(entries):
     matches = reversed(list(NUMBER_REGEX.finditer(entries[0].name)))
     for m in matches:
         pos = m.start()
         prefix = entries[0].name[:pos]
         if all(e.name.startswith(prefix) for e in entries):
-            entries_with_indices = []
-            indices = set()
+            entries_by_index = {}
             for e in entries:
                 n = NUMBER_REGEX.match(e.name[pos:])
                 if n is None:
                     return None
                 i = int(n.group())
-                if i in indices:
-                    return None
-                indices.add(i)
-                entries_with_indices.append((e, i))
-            entries_with_indices.sort(key=lambda ei: ei[1])
-            return [e for (e, i) in entries_with_indices]
+                entries_by_index.setdefault(i, []).append(e)
+            return entries_by_index
+
     return None
 
 def link_ordered_files(ordering, dest, start_index=0):