diff --git a/osu.Game/Beatmaps/BeatmapSetInfo.cs b/osu.Game/Beatmaps/BeatmapSetInfo.cs
index 79983becb0..1736e3fa90 100644
--- a/osu.Game/Beatmaps/BeatmapSetInfo.cs
+++ b/osu.Game/Beatmaps/BeatmapSetInfo.cs
@@ -5,7 +5,6 @@ using System.Collections.Generic;
 using System.ComponentModel.DataAnnotations.Schema;
 using System.Linq;
 using osu.Game.Database;
-using osu.Game.IO;
 
 namespace osu.Game.Beatmaps
 {
diff --git a/osu.Game/Database/IHasFiles.cs b/osu.Game/Database/IHasFiles.cs
new file mode 100644
index 0000000000..cae8ea66ef
--- /dev/null
+++ b/osu.Game/Database/IHasFiles.cs
@@ -0,0 +1,13 @@
+using System.Collections.Generic;
+
+namespace osu.Game.Database
+{
+    /// <summary>
+    /// A model that contains a list of files it is responsible for.
+    /// </summary>
+    /// <typeparam name="TFile">The model representing a file.</typeparam>
+    public interface IHasFiles<TFile>
+    {
+        List<TFile> Files { get; set; }
+    }
+}
diff --git a/osu.Game/Database/ISoftDelete.cs b/osu.Game/Database/ISoftDelete.cs
index 19510421c4..c884d7af00 100644
--- a/osu.Game/Database/ISoftDelete.cs
+++ b/osu.Game/Database/ISoftDelete.cs
@@ -3,8 +3,14 @@
 
 namespace osu.Game.Database
 {
+    /// <summary>
+    /// A model that can be deleted from user's view without being instantly lost.
+    /// </summary>
     public interface ISoftDelete
     {
+        /// <summary>
+        /// Whether this model is marked for future deletion.
+        /// </summary>
         bool DeletePending { get; set; }
     }
 }
diff --git a/osu.Game/Database/MutableDatabaseBackedStore.cs b/osu.Game/Database/MutableDatabaseBackedStore.cs
index 3905942c8c..96bc48fd8a 100644
--- a/osu.Game/Database/MutableDatabaseBackedStore.cs
+++ b/osu.Game/Database/MutableDatabaseBackedStore.cs
@@ -83,11 +83,7 @@ namespace osu.Game.Database
 
         protected virtual IQueryable<T> AddIncludesForDeletion(IQueryable<T> query) => query;
 
-        protected virtual void Purge(List<T> items, OsuDbContext context)
-        {
-            // cascades down to beatmaps.
-            context.RemoveRange(items);
-        }
+        protected virtual void Purge(List<T> items, OsuDbContext context) => context.RemoveRange(items);
 
         /// <summary>
         /// Purge items in a pending delete state.
diff --git a/osu.Game/IO/IHasFiles.cs b/osu.Game/IO/IHasFiles.cs
deleted file mode 100644
index df313b4eae..0000000000
--- a/osu.Game/IO/IHasFiles.cs
+++ /dev/null
@@ -1,9 +0,0 @@
-using System.Collections.Generic;
-
-namespace osu.Game.IO
-{
-    public interface IHasFiles<TFile>
-    {
-        List<TFile> Files { get; set; }
-    }
-}
diff --git a/osu.Game/osu.Game.csproj b/osu.Game/osu.Game.csproj
index bfe7ec1821..7e440dacf8 100644
--- a/osu.Game/osu.Game.csproj
+++ b/osu.Game/osu.Game.csproj
@@ -279,6 +279,7 @@
     <Compile Include="Database\DatabaseWriteUsage.cs" />
     <Compile Include="Database\ICanAcceptFiles.cs" />
     <Compile Include="Database\IDatabaseContextFactory.cs" />
+    <Compile Include="Database\IHasFiles.cs" />
     <Compile Include="Database\IHasPrimaryKey.cs" />
     <Compile Include="Database\INamedFileInfo.cs" />
     <Compile Include="Database\ISoftDelete.cs" />
@@ -289,7 +290,6 @@
     <Compile Include="IO\Archives\ArchiveReader.cs" />
     <Compile Include="IO\Archives\LegacyFilesystemReader.cs" />
     <Compile Include="IO\Archives\ZipArchiveReader.cs" />
-    <Compile Include="IO\IHasFiles.cs" />
     <Compile Include="Online\API\APIDownloadRequest.cs" />
     <Compile Include="Online\API\Requests\GetUserRequest.cs" />
     <Compile Include="Migrations\20180125143340_Settings.cs" />