diff --git a/ArcFormats/ArcFormats.csproj b/ArcFormats/ArcFormats.csproj
index 7c961497..68906f1f 100644
--- a/ArcFormats/ArcFormats.csproj
+++ b/ArcFormats/ArcFormats.csproj
@@ -124,6 +124,7 @@
     <Compile Include="Kaas\AudioKAAS.cs" />
     <Compile Include="Kaguya\ArcAN21.cs" />
     <Compile Include="Kaguya\ArcUF.cs" />
+    <Compile Include="KiriKiri\ArcXPK.cs" />
     <Compile Include="KiriKiri\CzCrypt.cs" />
     <Compile Include="Kurumi\ImageGRA.cs" />
     <Compile Include="Leaf\ArcPX.cs" />
diff --git a/ArcFormats/KiriKiri/ArcXPK.cs b/ArcFormats/KiriKiri/ArcXPK.cs
new file mode 100644
index 00000000..bd3b0706
--- /dev/null
+++ b/ArcFormats/KiriKiri/ArcXPK.cs
@@ -0,0 +1,89 @@
+//! \file       ArcXPK.cs
+//! \date       2017 Dec 05
+//! \brief      KAG System resource archive.
+//
+// Copyright (C) 2017 by morkt
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to
+// deal in the Software without restriction, including without limitation the
+// rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
+// sell copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in
+// all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+// FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+// IN THE SOFTWARE.
+//
+
+using System.Collections.Generic;
+using System.ComponentModel.Composition;
+using System.Text;
+using GameRes.Utility;
+
+namespace GameRes.Formats.KiriKiri
+{
+    [Export(typeof(ArchiveFormat))]
+    public class XpkOpener : ArchiveFormat
+    {
+        public override string         Tag { get { return "XPK"; } }
+        public override string Description { get { return "KAG System resource archive"; } }
+        public override uint     Signature { get { return 0x314B5058; } } // 'XPK1'
+        public override bool  IsHierarchic { get { return true; } }
+        public override bool      CanWrite { get { return false; } }
+
+        public XpkOpener ()
+        {
+            Signatures = new uint[] { 0x314B5058, 0 };
+        }
+
+        static readonly byte[] SignatureBytes = Encoding.ASCII.GetBytes ("XPK1\x1A");
+
+        public override ArcFile TryOpen (ArcView file)
+        {
+            long base_offset = 0;
+            if (0x5A4D == file.View.ReadUInt16 (0)) // 'MZ'
+                base_offset = Xp3Opener.SkipExeHeader (file, SignatureBytes);
+            if (!file.View.BytesEqual (base_offset, SignatureBytes))
+                return null;
+            using (var index = file.CreateStream())
+            {
+                index.Position = base_offset+10;
+                int count = (int)ReadUInt (index);
+                if (!IsSaneCount (count))
+                    return null;
+                var dir = new List<Entry> (count);
+                for (int i = 0; i < count; ++i)
+                {
+                    long offset = ReadUInt (index) + base_offset;
+                    uint size = ReadUInt (index);
+                    uint unpacked_size = ReadUInt (index);
+                    index.ReadInt16();
+                    var name = index.ReadCString();
+                    var entry = FormatCatalog.Instance.Create<PackedEntry> (name);
+                    entry.Offset = offset;
+                    entry.Size   = size;
+                    entry.UnpackedSize = unpacked_size;
+                    if (!entry.CheckPlacement (file.MaxOffset) && !(offset == file.MaxOffset && size == 0))
+                        return null;
+                    dir.Add (entry);
+                }
+                return new ArcFile (file, this, dir);
+            }
+        }
+
+        internal static uint ReadUInt (IBinaryStream input)
+        {
+            if (input.ReadByte() != 4)
+                throw new InvalidFormatException();
+            return Binary.BigEndian (input.ReadUInt32());
+        }
+    }
+}