diff --git a/Gemfile b/Gemfile
index 6bcb96a..bea2d7b 100644
--- a/Gemfile
+++ b/Gemfile
@@ -1,73 +1,34 @@
-source "https://rubygems.org"
+source 'https://rubygems.org'
 
-ruby "3.3.4"
+ruby '3.3.4'
+gem 'acts-as-taggable-on'
+gem 'bootsnap', require: false
+gem 'importmap-rails'
+gem 'jbuilder'
+gem 'money'
+gem 'pg', '~> 1.1'
+gem 'puma', '>= 5.0'
+gem 'rails', '~> 7.1.3', '>= 7.1.3.2'
+gem 'redis', '>= 4.0.1'
+gem 'sprockets-rails'
+gem 'stimulus-rails'
+gem 'turbo-rails'
+gem 'tzinfo-data', platforms: %i[windows jruby]
 
-# Bundle edge Rails instead: gem "rails", github: "rails/rails", branch: "main"
-gem "rails", "~> 7.1.3", ">= 7.1.3.2"
-
-# The original asset pipeline for Rails [https://github.com/rails/sprockets-rails]
-gem "sprockets-rails"
-
-# Use postgresql as the database for Active Record
-gem "pg", "~> 1.1"
-
-# Use the Puma web server [https://github.com/puma/puma]
-gem "puma", ">= 5.0"
-
-# Use JavaScript with ESM import maps [https://github.com/rails/importmap-rails]
-gem "importmap-rails"
-
-# Hotwire's SPA-like page accelerator [https://turbo.hotwired.dev]
-gem "turbo-rails"
-
-# Hotwire's modest JavaScript framework [https://stimulus.hotwired.dev]
-gem "stimulus-rails"
-
-# Build JSON APIs with ease [https://github.com/rails/jbuilder]
-gem "jbuilder"
-
-# Use Redis adapter to run Action Cable in production
-gem "redis", ">= 4.0.1"
-
-# Use Kredis to get higher-level data types in Redis [https://github.com/rails/kredis]
-# gem "kredis"
-
-# Use Active Model has_secure_password [https://guides.rubyonrails.org/active_model_basics.html#securepassword]
-# gem "bcrypt", "~> 3.1.7"
-
-# Windows does not include zoneinfo files, so bundle the tzinfo-data gem
-gem "tzinfo-data", platforms: %i[ windows jruby ]
-
-# Reduces boot times through caching; required in config/boot.rb
-gem "bootsnap", require: false
-
-# Use Active Storage variants [https://guides.rubyonrails.org/active_storage_overview.html#transforming-images]
-# gem "image_processing", "~> 1.2"
+gem 'jsonapi-rails'
+gem 'rack-cors'
+gem 'react-rails'
+gem 'rubytree'
 
 group :development, :test do
-  # See https://guides.rubyonrails.org/debugging_rails_applications.html#debugging-with-the-debug-gem
-  gem "debug", platforms: %i[ mri windows ]
-  gem 'rspec-rails', '~> 6.1.0'
+  gem 'debug', platforms: %i[mri windows]
+  gem 'factory_bot_rails'
   gem 'faker'
   gem 'pry'
-  gem "factory_bot_rails"
+  gem 'rspec-rails', '~> 6.1.0'
 end
 
 group :development do
-  # Use console on exceptions pages [https://github.com/rails/web-console]
-  gem "web-console"
-
-  # Add speed badges [https://github.com/MiniProfiler/rack-mini-profiler]
-  # gem "rack-mini-profiler"
-
-  # Speed up commands on slow machines / big apps [https://github.com/rails/spring]
-  # gem "spring"
+  gem 'rubocop'
+  gem 'web-console'
 end
-
-gem "money"
-gem 'acts-as-taggable-on'
-
-gem "rubytree"
-gem 'react-rails'
-gem 'rack-cors'
-gem 'jsonapi-rails'
\ No newline at end of file
diff --git a/Gemfile.lock b/Gemfile.lock
index 90dbe8c..0e23ca2 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -77,6 +77,7 @@ GEM
       tzinfo (~> 2.0)
     acts-as-taggable-on (10.0.0)
       activerecord (>= 6.1, < 7.2)
+    ast (2.4.2)
     babel-source (5.8.35)
     babel-transpiler (0.7.0)
       babel-source (>= 4.0, < 6)
@@ -133,6 +134,7 @@ GEM
     jsonapi-renderer (0.2.2)
     jsonapi-serializable (0.3.1)
       jsonapi-renderer (~> 0.2.0)
+    language_server-protocol (3.17.0.3)
     loofah (2.22.0)
       crass (~> 1.0.2)
       nokogiri (>= 1.12.0)
@@ -171,6 +173,10 @@ GEM
       racc (~> 1.4)
     nokogiri (1.16.7-x86_64-linux)
       racc (~> 1.4)
+    parallel (1.26.2)
+    parser (3.3.4.2)
+      ast (~> 2.4.1)
+      racc
     pg (1.5.7)
     pry (0.14.2)
       coderay (~> 1.1)
@@ -219,6 +225,7 @@ GEM
       rake (>= 12.2)
       thor (~> 1.0, >= 1.2.2)
       zeitwerk (~> 2.6)
+    rainbow (3.1.1)
     rake (13.2.1)
     rdoc (6.7.0)
       psych (>= 4.0.0)
@@ -232,8 +239,10 @@ GEM
       redis-client (>= 0.22.0)
     redis-client (0.22.2)
       connection_pool
+    regexp_parser (2.9.2)
     reline (0.5.9)
       io-console (~> 0.5)
+    rexml (3.2.8)
     rspec-core (3.12.3)
       rspec-support (~> 3.12.0)
     rspec-expectations (3.12.4)
@@ -251,6 +260,20 @@ GEM
       rspec-mocks (~> 3.12)
       rspec-support (~> 3.12)
     rspec-support (3.12.2)
+    rubocop (1.65.1)
+      json (~> 2.3)
+      language_server-protocol (>= 3.17.0)
+      parallel (~> 1.10)
+      parser (>= 3.3.0.2)
+      rainbow (>= 2.2.2, < 4.0)
+      regexp_parser (>= 2.4, < 3.0)
+      rexml (>= 3.2.5, < 4.0)
+      rubocop-ast (>= 1.31.1, < 2.0)
+      ruby-progressbar (~> 1.7)
+      unicode-display_width (>= 2.4.0, < 3.0)
+    rubocop-ast (1.32.0)
+      parser (>= 3.3.1.0)
+    ruby-progressbar (1.13.0)
     rubytree (2.0.3)
       json (~> 2.0, > 2.3.1)
     sprockets (4.2.1)
@@ -272,6 +295,7 @@ GEM
       railties (>= 6.0.0)
     tzinfo (2.0.6)
       concurrent-ruby (~> 1.0)
+    unicode-display_width (2.5.0)
     web-console (4.2.1)
       actionview (>= 6.0.0)
       activemodel (>= 6.0.0)
@@ -309,6 +333,7 @@ DEPENDENCIES
   react-rails
   redis (>= 4.0.1)
   rspec-rails (~> 6.1.0)
+  rubocop
   rubytree
   sprockets-rails
   stimulus-rails
diff --git a/app/controllers/groups_controller.rb b/app/controllers/groups_controller.rb
index 461a67f..0f489fb 100644
--- a/app/controllers/groups_controller.rb
+++ b/app/controllers/groups_controller.rb
@@ -1,5 +1,6 @@
 class GroupsController < ApplicationController
   def index
-    render jsonapi: Group.where(parent_id: nil), include: [children: [children: [:children]]]
+    roots = Group.where(parent_id: nil)
+    render jsonapi: roots, include: [children: [children: [:children]]]
   end
 end
diff --git a/app/controllers/guests_controller.rb b/app/controllers/guests_controller.rb
index 77298d6..925770f 100644
--- a/app/controllers/guests_controller.rb
+++ b/app/controllers/guests_controller.rb
@@ -6,14 +6,10 @@ class GuestsController < ApplicationController
   # GET /guests or /guests.json
   def index
     @guests = Guest.all
-                   .left_outer_joins(:affinity_groups)
-                   .order('tags.name' => :asc)
-                   .includes(:affinity_groups, :unbreakable_bonds)
+                   .joins(:group)
+                   .order('groups.name' => :asc)
 
-                   respond_to do |format|
-                      format.html
-                      format.json { render jsonapi: @guests }
-                   end
+      render jsonapi: @guests
   end
 
   # GET /guests/1 or /guests/1.json
diff --git a/app/models/group.rb b/app/models/group.rb
index 5a2e844..afcadaa 100644
--- a/app/models/group.rb
+++ b/app/models/group.rb
@@ -1,7 +1,9 @@
 class Group < ApplicationRecord
-    validates :name, uniqueness: true
-    validates :name, :order, presence: true
+  validates :name, uniqueness: true
+  validates :name, :order, presence: true
 
-    has_many :children, class_name: 'Group', foreign_key: 'parent_id'
-    belongs_to :parent, class_name: 'Group', optional: true
+  has_many :children, class_name: 'Group', foreign_key: 'parent_id'
+  belongs_to :parent, class_name: 'Group', optional: true
+
+  has_many :guests
 end
diff --git a/app/models/guest.rb b/app/models/guest.rb
index 60e3bc2..927a589 100644
--- a/app/models/guest.rb
+++ b/app/models/guest.rb
@@ -1,6 +1,6 @@
 class Guest < ApplicationRecord
   acts_as_taggable_on :affinity_groups, :unbreakable_bonds
-  
+  belongs_to :group
   def full_name
     "#{first_name} #{last_name}"
   end
diff --git a/app/serializers/serializable_group.rb b/app/serializers/serializable_group.rb
index e90dc52..f832475 100644
--- a/app/serializers/serializable_group.rb
+++ b/app/serializers/serializable_group.rb
@@ -4,4 +4,8 @@ class SerializableGroup < JSONAPI::Serializable::Resource
   attributes :name, :icon
 
   has_many :children
+
+  attribute :guest_count do
+    @object.guests.count
+  end
 end
diff --git a/app/serializers/serializable_guest.rb b/app/serializers/serializable_guest.rb
index c1e4bcc..3311d8b 100644
--- a/app/serializers/serializable_guest.rb
+++ b/app/serializers/serializable_guest.rb
@@ -1,9 +1,13 @@
 class SerializableGuest < JSONAPI::Serializable::Resource
   type 'guest'
 
-  attributes :id, :email
+  attributes :id, :email, :group_id
 
   attribute :name do
     "#{@object.first_name} #{@object.last_name}"
   end
+
+  attribute :group_name do
+    @object.group.name
+  end
 end
diff --git a/db/migrate/20240811154115_add_group_to_guest.rb b/db/migrate/20240811154115_add_group_to_guest.rb
new file mode 100644
index 0000000..d4e2bd4
--- /dev/null
+++ b/db/migrate/20240811154115_add_group_to_guest.rb
@@ -0,0 +1,5 @@
+class AddGroupToGuest < ActiveRecord::Migration[7.1]
+  def change
+    add_reference :guests, :group, null: false, foreign_key: true, type: :uuid
+  end
+end
diff --git a/db/schema.rb b/db/schema.rb
index 00b4b60..47376a1 100644
--- a/db/schema.rb
+++ b/db/schema.rb
@@ -10,7 +10,7 @@
 #
 # It's strongly recommended that you check this file into your version control system.
 
-ActiveRecord::Schema[7.1].define(version: 2024_08_11_143801) do
+ActiveRecord::Schema[7.1].define(version: 2024_08_11_154115) do
   # These are extensions that must be enabled in order to support this database
   enable_extension "plpgsql"
 
@@ -44,6 +44,8 @@ ActiveRecord::Schema[7.1].define(version: 2024_08_11_143801) do
     t.string "phone"
     t.datetime "created_at", null: false
     t.datetime "updated_at", null: false
+    t.uuid "group_id", null: false
+    t.index ["group_id"], name: "index_guests_on_group_id"
   end
 
   create_table "seats", id: :uuid, default: -> { "gen_random_uuid()" }, force: :cascade do |t|
@@ -94,6 +96,7 @@ ActiveRecord::Schema[7.1].define(version: 2024_08_11_143801) do
   end
 
   add_foreign_key "groups", "groups", column: "parent_id"
+  add_foreign_key "guests", "groups"
   add_foreign_key "seats", "guests"
   add_foreign_key "seats", "tables_arrangements", on_delete: :cascade
   add_foreign_key "taggings", "tags"
diff --git a/db/seeds.rb b/db/seeds.rb
index 5103a7d..53c3376 100644
--- a/db/seeds.rb
+++ b/db/seeds.rb
@@ -22,82 +22,44 @@ Expense.create!(name: 'Transportation', amount: 3000, pricing_type: 'fixed')
 Expense.create!(name: 'Invitations', amount: 200, pricing_type: 'fixed')
 Expense.create!(name: 'Cake', amount: 500, pricing_type: 'fixed')
 
-Group.create!(name: "Jim's guests", icon: "pi pi-heart").tap do |parent|
-  parent.children.create!(name: "Jim's family", icon: "pi pi-users").tap do |family|
-    family.children.create!(name: "Jim's close family", icon: "pi pi-home")
-    family.children.create!(name: "Jim's cousins", icon: "pi pi-home")
-    family.children.create!(name: "Jim's relatives", icon: "pi pi-home")
+Group.create!(name: "Jim's guests", icon: 'pi pi-heart').tap do |parent|
+  parent.children.create!(name: "Jim's family", icon: 'pi pi-users').tap do |family|
+    family.children.create!(name: "Jim's close family", icon: 'pi pi-home')
+    family.children.create!(name: "Jim's cousins", icon: 'pi pi-home')
+    family.children.create!(name: "Jim's relatives", icon: 'pi pi-home')
   end
-  parent.children.create!(name: "Jim's friends", icon: "pi pi-bullseye")
-  parent.children.create!(name: "Jim's work", icon: "pi pi-desktop").tap do |work|
-    work.children.create!(name: "Jim's besties at work", icon: "pi pi-briefcase")
-  end  
-end
-
-Group.create!(name: "Pam's guests", icon: "pi pi-heart-fill").tap do |parent|
-  parent.children.create!(name: "Pam's family", icon: "pi pi-users").tap do |family|
-    family.children.create!(name: "Pam's close family", icon: "pi pi-home")
-    family.children.create!(name: "Pam's cousins", icon: "pi pi-home")
-    family.children.create!(name: "Pam's relatives", icon: "pi pi-home")
+  parent.children.create!(name: "Jim's friends", icon: 'pi pi-bullseye')
+  parent.children.create!(name: "Jim's work", icon: 'pi pi-desktop').tap do |work|
+    work.children.create!(name: "Jim's besties at work", icon: 'pi pi-briefcase')
   end
-  parent.children.create!(name: "Pam's friends", icon: "pi pi-bullseye")
-  parent.children.create!(name: "Pam's work", icon: "pi pi-desktop").tap do |work|
-    work.children.create!(name: "Pam's besties at work", icon: "pi pi-briefcase")
-  end  
 end
 
-Group.create!(name: "Common guests", icon: "pi pi-users").tap do |parent|
-  parent.children.create!(name: "College friends", icon: "pi pi-calculator")
-  parent.children.create!(name: "High school friends", icon: "pi pi-crown")
-  parent.children.create!(name: "Childhood friends", icon: "pi pi-envelope")
+Group.create!(name: "Pam's guests", icon: 'pi pi-heart-fill').tap do |parent|
+  parent.children.create!(name: "Pam's family", icon: 'pi pi-users').tap do |family|
+    family.children.create!(name: "Pam's close family", icon: 'pi pi-home')
+    family.children.create!(name: "Pam's cousins", icon: 'pi pi-home')
+    family.children.create!(name: "Pam's relatives", icon: 'pi pi-home')
+  end
+  parent.children.create!(name: "Pam's friends", icon: 'pi pi-bullseye')
+  parent.children.create!(name: "Pam's work", icon: 'pi pi-desktop').tap do |work|
+    work.children.create!(name: "Pam's besties at work", icon: 'pi pi-briefcase')
+  end
 end
 
-samples = {
-  close_family_a: 10,
-  close_family_b: 10,
-  cousins_a: 20,
-  cousins_b: 15,
-  relatives_a: 15,
-  relatives_b: 10,
-  work_a: 10,
-  work_b: 10,
-  besties_work_a: 5,
-  besties_work_b: 5,
-  college_friends_a: 10,
-  college_friends_b: 10,
-  high_school_friends_a: 10,
-  high_school_friends_b: 10,
-  childhood_friends_a: 10,
-  childhood_friends_b: 10,
-  basket_team_a: 10,
-  football_team_a: 15,
-  dance_club: 10
-}.each_with_object([]) do |(affinity_group, count), acc|
-  count.times { acc << affinity_group }
+Group.create!(name: 'Common guests', icon: 'pi pi-users').tap do |parent|
+  parent.children.create!(name: 'College friends', icon: 'pi pi-calculator')
+  parent.children.create!(name: 'High school friends', icon: 'pi pi-crown')
+  parent.children.create!(name: 'Childhood friends', icon: 'pi pi-envelope')
 end
 
+groups = Group.all
+
 NUMBER_OF_GUESTS.times do
-  guest = Guest.create!(first_name: Faker::Name.first_name,
-                        last_name: Faker::Name.last_name,
-                        email: Faker::Internet.email,
-                        phone: Faker::PhoneNumber.cell_phone)
-
-  guest.affinity_group_list.add(samples.sample)
-  guest.save!
-end
-
-# Add unbreakable bonds
-Guest.affinity_group_counts.each do |group|
-  couples = (group.taggings_count / 4).floor
-
-  guests_involved = Guest.tagged_with(group.name).limit(couples * 2)
-  guests_involved.each_slice(2) do |a, b|
-    bond_name = "#{a.full_name} & #{b.full_name}"
-
-    a.unbreakable_bond_list.add(bond_name)
-    b.unbreakable_bond_list.add(bond_name)
-
-    a.save!
-    b.save!
-  end
+  Guest.create!(
+    first_name: Faker::Name.first_name,
+    last_name: Faker::Name.last_name,
+    email: Faker::Internet.email,
+    phone: Faker::PhoneNumber.cell_phone,
+    group: groups.sample
+  )
 end
diff --git a/spec/factories/groups.rb b/spec/factories/groups.rb
index a8fe677..9bfade0 100644
--- a/spec/factories/groups.rb
+++ b/spec/factories/groups.rb
@@ -1,7 +1,6 @@
 FactoryBot.define do
   factory :group do
-    name { "MyString" }
-    icon { "MyString" }
+    sequence(:name) { |i| "Group #{i}" }
     order { 1 }
   end
 end
diff --git a/spec/factories/guest.rb b/spec/factories/guest.rb
index f761dd9..7ff9066 100644
--- a/spec/factories/guest.rb
+++ b/spec/factories/guest.rb
@@ -1,5 +1,7 @@
 FactoryBot.define do
   factory :guest do
+    association :group
+
     first_name { Faker::Name.first_name }
     last_name { Faker::Name.last_name }
     email { Faker::Internet.email }