diff --git a/ArcFormats/ShiinaRio/WarcEncryption.cs b/ArcFormats/ShiinaRio/WarcEncryption.cs
index f461a064..b541c6cd 100644
--- a/ArcFormats/ShiinaRio/WarcEncryption.cs
+++ b/ArcFormats/ShiinaRio/WarcEncryption.cs
@@ -1355,4 +1355,44 @@ namespace GameRes.Formats.ShiinaRio
             throw new NotImplementedException ();
         }
     }
+
+    [Serializable]
+    public class SaiminCrypt : IDecryptExtra
+    {
+        public void Decrypt (byte[] data, int index, uint length, uint flags)
+        {
+            byte[] key = new byte[]
+            {
+                0x81, 0x75, 0x89, 0xBD, 0x82, 0xA9, 0x91, 0xE5,
+                0x82, 0xAB, 0x82, 0xC8, 0x8E, 0x96, 0x82, 0xF0,
+                0x90, 0xAC, 0x82, 0xB5, 0x90, 0x8B, 0x82, 0xB0,
+                0x82, 0xBD, 0x8B, 0x43, 0x95, 0xAA, 0x82, 0xC5,
+                0x83, 0x51, 0x83, 0x5C, 0x81, 0x49, 0x81, 0x76,
+                0x81, 0x75, 0x82, 0xC7, 0x82, 0xEA, 0x82, 0xBE,
+                0x82, 0xAF, 0x92, 0xE1, 0x92, 0xC0, 0x82, 0xC5,
+                0x93, 0xAD, 0x82, 0xA9, 0x82, 0xB9, 0x82, 0xE9,
+                0x82, 0xC2, 0x82, 0xE0, 0x82, 0xE8, 0x82, 0xC5,
+                0x83, 0x51, 0x83, 0x5C, 0x21, 0x21, 0x81, 0x76
+            };
+
+            if (length >= 0x200)
+            {
+                if ((flags & 0x202) == 0x202)
+                {
+                    for (int i = 0; i < ((length & 0x7E) | 1); i++)
+                    {
+                        data[index+i] ^= key[i % 0x40];
+                    }
+                    var value = MemoryMarshal.Read<uint> (data.AsSpan(index+0x104));
+                    value ^= length;
+                    MemoryMarshal.Write<uint> (data.AsSpan (index+0x104), ref value);
+                }
+            }
+        }
+
+        public void Encrypt (byte[] data, int index, uint length, uint flags)
+        {
+            throw new NotImplementedException ();
+        }
+    }
 }