diff --git a/assets/less/mio/classes/profile/header.less b/assets/less/mio/classes/profile/header.less
index f4f4b00a..f44f5da0 100644
--- a/assets/less/mio/classes/profile/header.less
+++ b/assets/less/mio/classes/profile/header.less
@@ -46,6 +46,7 @@
             border-radius: 2px;
             line-height: 1.2em;
             padding: 1px 5px 4px;
+            cursor: default;
         }
     }
 
@@ -98,6 +99,7 @@
         color: inherit;
         text-decoration: none;
         padding: 10px;
+        cursor: default;
 
         &--date {
             min-width: 130px;
@@ -106,11 +108,13 @@
         &__name {
             font-size: .9em;
             font-variant: small-caps;
+            cursor: inherit;
         }
 
         &__value {
             font-size: 1.3em;
             text-align: right;
+            cursor: inherit;
         }
     }
 
diff --git a/database/2018_09_17_195802_add_relations_table.php b/database/2018_09_17_195802_add_relations_table.php
new file mode 100644
index 00000000..9d57e1af
--- /dev/null
+++ b/database/2018_09_17_195802_add_relations_table.php
@@ -0,0 +1,33 @@
+<?php
+namespace Misuzu\DatabaseMigrations\AddRelationsTable;
+
+use PDO;
+
+function migrate_up(PDO $conn): void
+{
+    $conn->exec('
+        CREATE TABLE `msz_user_relations` (
+            `user_id`           INT(10)     UNSIGNED    NOT NULL,
+            `subject_id`        INT(10)     UNSIGNED    NOT NULL,
+            `relation_type`     TINYINT(3)  UNSIGNED    NOT NULL,
+            `relation_created`  TIMESTAMP               NOT NULL DEFAULT CURRENT_TIMESTAMP,
+            UNIQUE  INDEX `user_relations_unique`               (`user_id`, `subject_id`),
+                    INDEX `user_relations_subject_id_foreign`   (`subject_id`),
+            CONSTRAINT `user_relations_subject_id_foreign`
+                FOREIGN KEY (`subject_id`)
+                REFERENCES `msz_users` (`user_id`)
+                ON UPDATE CASCADE
+                ON DELETE CASCADE,
+            CONSTRAINT `user_relations_user_id_foreign`
+                FOREIGN KEY (`user_id`)
+                REFERENCES `msz_users` (`user_id`)
+                ON UPDATE CASCADE
+                ON DELETE CASCADE
+        )
+    ');
+}
+
+function migrate_down(PDO $conn): void
+{
+    $conn->exec('DROP TABLE `msz_user_relations`');
+}
diff --git a/misuzu.php b/misuzu.php
index 05baf9d4..dae0df08 100644
--- a/misuzu.php
+++ b/misuzu.php
@@ -42,6 +42,7 @@ require_once __DIR__ . '/src/Forum/topic.php';
 require_once __DIR__ . '/src/Forum/validate.php';
 require_once __DIR__ . '/src/Users/login_attempt.php';
 require_once __DIR__ . '/src/Users/profile.php';
+require_once __DIR__ . '/src/Users/relations.php';
 require_once __DIR__ . '/src/Users/role.php';
 require_once __DIR__ . '/src/Users/session.php';
 require_once __DIR__ . '/src/Users/user.php';
diff --git a/public/profile.php b/public/profile.php
index e6b60cb8..e560d674 100644
--- a/public/profile.php
+++ b/public/profile.php
@@ -94,6 +94,36 @@ switch ($mode) {
             break;
         }
 
+        if ($app->hasActiveSession()) {
+            $getFriendInfo = Database::prepare('
+                SELECT
+                    :visitor as `visitor`, :profile as `profile`,
+                    (
+                        SELECT `relation_type`
+                        FROM `msz_user_relations`
+                        WHERE `user_id` = `visitor`
+                        AND `subject_id` = `profile`
+                    ) as `visitor_relation`,
+                    (
+                        SELECT `relation_type`
+                        FROM `msz_user_relations`
+                        WHERE `subject_id` = `visitor`
+                        AND `user_id` = `profile`
+                    ) as `profile_relation`,
+                    (
+                        SELECT MAX(`relation_created`)
+                        FROM `msz_user_relations`
+                        WHERE (`user_id` = `visitor` AND `subject_id` = `profile`)
+                        OR (`user_id` = `profile` AND `subject_id` = `visitor`)
+                    ) as `relation_created`
+            ');
+            $getFriendInfo->bindValue('visitor', $app->getUserId());
+            $getFriendInfo->bindValue('profile', $profile['user_id']);
+            $friendInfo = $getFriendInfo->execute() ? $getFriendInfo->fetch(PDO::FETCH_ASSOC) : [];
+
+            tpl_var('friend_info', $friendInfo);
+        }
+
         tpl_vars([
             'profile' => $profile,
             'profile_fields' => $app->hasActiveSession() ? user_profile_fields_display($profile) : [],
diff --git a/public/relations.php b/public/relations.php
new file mode 100644
index 00000000..1e7165cf
--- /dev/null
+++ b/public/relations.php
@@ -0,0 +1,41 @@
+<?php
+use Misuzu\Database;
+
+require_once __DIR__ . '/../misuzu.php';
+
+if (empty($_SERVER['HTTP_REFERER']) || !is_local_url($_SERVER['HTTP_REFERER'])) {
+    header('Location: /');
+    return;
+}
+
+if (!$app->hasActiveSession()) {
+    echo render_error(403);
+    return;
+}
+
+$subjectId = (int)($_GET['u'] ?? 0);
+
+switch ($_GET['m'] ?? null) {
+    case 'add':
+        switch ($_GET['t'] ?? null) {
+            case 'follow':
+            default:
+                $type = MSZ_USER_RELATION_FOLLOW;
+                break;
+        }
+
+        if (user_relation_add($app->getUserId(), $subjectId, $type) !== MSZ_USER_RELATION_E_OK) {
+            echo render_error(500);
+            return;
+        }
+        break;
+
+    case 'remove':
+        if (!user_relation_remove($app->getUserId(), $subjectId)) {
+            echo render_error(500);
+            return;
+        }
+        break;
+}
+
+header('Location: ' . $_SERVER['HTTP_REFERER']);
diff --git a/src/Users/relations.php b/src/Users/relations.php
new file mode 100644
index 00000000..9d0f0414
--- /dev/null
+++ b/src/Users/relations.php
@@ -0,0 +1,56 @@
+<?php
+use Misuzu\Database;
+
+define('MSZ_USER_RELATION_FOLLOW', 1);
+
+define('MSZ_USER_RELATION_TYPES', [
+    MSZ_USER_RELATION_FOLLOW,
+]);
+
+define('MSZ_USER_RELATION_E_OK', 0);
+define('MSZ_USER_RELATION_E_USER_ID', 1);
+define('MSZ_USER_RELATION_E_DATABASE', 2);
+define('MSZ_USER_RELATION_E_INVALID_TYPE', 2);
+
+function user_relation_add(int $userId, int $subjectId, int $type = MSZ_USER_RELATION_FOLLOW): int
+{
+    if ($userId < 1 || $subjectId < 1) {
+        return MSZ_USER_RELATION_E_USER_ID;
+    }
+
+    if (!in_array($type, MSZ_USER_RELATION_TYPES, true)) {
+        return MSZ_USER_RELATION_E_INVALID_TYPE;
+    }
+
+    $addRelation = Database::prepare('
+        REPLACE INTO `msz_user_relations`
+            (`user_id`, `subject_id`, `relation_type`)
+        VALUES
+            (:user_id, :subject_id, :type)
+    ');
+    $addRelation->bindValue('user_id', $userId);
+    $addRelation->bindValue('subject_id', $subjectId);
+    $addRelation->bindValue('type', $type);
+    $addRelation->execute();
+
+    return $addRelation->execute()
+        ? MSZ_USER_RELATION_E_OK
+        : MSZ_USER_RELATION_E_DATABASE;
+}
+
+function user_relation_remove(int $userId, int $subjectId): bool
+{
+    if ($userId < 1 || $subjectId < 1) {
+        return false;
+    }
+
+    $removeRelation = Database::prepare('
+        DELETE FROM `msz_user_relations`
+        WHERE `user_id` = :user_id
+        AND `subject_id` = :subject_id
+    ');
+    $removeRelation->bindValue('user_id', $userId);
+    $removeRelation->bindValue('subject_id', $subjectId);
+
+    return $removeRelation->execute();
+}
diff --git a/templates/user/profile.twig b/templates/user/profile.twig
index 37263a8f..c53b6f67 100644
--- a/templates/user/profile.twig
+++ b/templates/user/profile.twig
@@ -38,18 +38,29 @@
                     </div>
                 </div>
 
-                <!--div class="profile__header__details__relation">
-                    Follows you
-                </div-->
+                {% if friend_info is defined and (friend_info.profile_relation is not null or friend_info.visitor_relation is not null) %}
+                    <div class="profile__header__details__relation" title="Since {{ friend_info.relation_created|date('r') }}">
+                        {% if friend_info.profile_relation and friend_info.visitor_relation %}
+                            Mutual Friends
+                        {% elseif friend_info.visitor_relation %}
+                            You Follow
+                        {% elseif friend_info.profile_relation %}
+                            Follows You
+                        {% endif %}
+                    </div>
+                {% endif %}
             </div>
 
             <div class="profile__header__options">
                 <div class="profile__header__actions">
                     {% if current_user.user_id|default(0) == profile.user_id %}
                         <a href="/settings.php" class="profile__header__action">Edit Profile</a>
-                    {# else %}
-                        <a href="#" class="profile__header__action">Add Friend</a>
-                        <a href="#" class="profile__header__action profile__header__action--destroy">Unfriend</a>#}
+                    {% elseif current_user is defined %}
+                        {% if friend_info.visitor_relation %}
+                            <a href="/relations.php?u={{ profile.user_id }}&amp;m=remove" class="profile__header__action profile__header__action--destroy">Unfriend</a>
+                        {% else %}
+                            <a href="/relations.php?u={{ profile.user_id }}&amp;m=add&amp;t=follow" class="profile__header__action">Add Friend</a>
+                        {% endif %}
                     {% endif %}
                 </div>
 
diff --git a/utility.php b/utility.php
index 6bc633e2..ef81fba8 100644
--- a/utility.php
+++ b/utility.php
@@ -423,3 +423,8 @@ function snake_to_camel(string $snake): string
 {
     return str_replace('_', '', ucwords($snake, '_'));
 }
+
+function is_user_int($value): bool
+{
+    return ctype_digit(strval($value));
+}